Update deps

Website

.cargo/config.toml

@@ -0,0 +1,2 @@
+[alias]
+dev = ["run", "--", "dev"]

.editorconfig

@@ -1,7 +0,0 @@
-root = true
-
-[*.rs]
-end_of_line = lf
-insert_final_newfile = true
-indent_style = space
-indent_size = 4

.github/workflows/rust.yml

@@ -0,0 +1,47 @@
+name: Check
+
+on:
+  push:
+    branches: [main]
+    paths-ignore:
+      - website
+      - '*.md'
+  pull_request:
+    branches: [main]
+    paths-ignore:
+      - website
+      - '*.md'
+
+env:
+  CARGO_TERM_COLOR: always
+
+jobs:
+  clippy:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Clippy
+        run: cargo clippy -- --deny warnings
+  fmt:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: rustfmt
+        run: cargo fmt --all --check
+  test:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-latest, windows-latest, macos-latest]
+    steps:
+      - uses: actions/checkout@v4
+      - uses: swatinem/rust-cache@v2
+      - name: cargo test
+        run: cargo test --workspace
+  dev-check:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: swatinem/rust-cache@v2
+      - name: rustlings dev check
+        run: cargo dev check --require-solutions

.github/workflows/website.yml

@@ -0,0 +1,43 @@
+name: Website
+
+on:
+  workflow_dispatch:
+  push:
+    branches: [main]
+    paths: [website]
+
+jobs:
+  build:
+    defaults:
+      run:
+        working-directory: website
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install TailwindCSS
+        run: npm install
+      - name: Build CSS
+        run: npx @tailwindcss/cli -m -i input.css -o static/main.css
+      - name: Download Zola
+        run: curl -fsSL https://github.com/getzola/zola/releases/download/v0.20.0/zola-v0.20.0-x86_64-unknown-linux-gnu.tar.gz | tar xz
+      - name: Build site
+        run: ./zola build
+      - name: Upload static files as artifact
+        uses: actions/upload-pages-artifact@v3
+        with:
+          path: website/public/
+
+  deploy:
+    needs: build
+    # Grant GITHUB_TOKEN the permissions required to make a Pages deployment
+    permissions:
+      pages: write    # to deploy to Pages
+      id-token: write # to verify the deployment originates from an appropriate source
+    # Deploy to the github-pages environment
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+    runs-on: ubuntu-latest
+    steps:
+      - name: Deploy to GitHub Pages
+        uses: actions/deploy-pages@v4

.gitignore

@@ -1,11 +1,19 @@
-*.swp
+# Cargo
 target/
-**/*.rs.bk
+Cargo.lock
+!/Cargo.lock
+
+# State file
+.rustlings-state.txt
+
+# OS
 .DS_Store
-*.pdb
-exercises/clippy/Cargo.toml
-exercises/clippy/Cargo.lock
-rust-project.json
+.direnv/
+
+# Editor
+*.swp
 .idea
-.vscode
 *.iml
+
+# Ignore file for editors like Helix
+.ignore

.gitpod.yml

@@ -1,7 +0,0 @@
-tasks:
-  - init: /workspace/rustlings/install.sh
-    command: /workspace/.cargo/bin/rustlings watch
-
-vscode:
-  extensions:
-    - rust-lang.rust@0.7.8

.replit

@@ -1,2 +0,0 @@
-language = "rust"
-run = "[ -x ~/.cargo/bin/rustlings ] && ~/.cargo/bin/rustlings watch || ./install.sh"

.typos.toml

@@ -0,0 +1,7 @@
+[default.extend-words]
+"earch" = "earch" # Because of <s>earch in the list footer
+
+[files]
+extend-exclude = [
+  "CHANGELOG.md",
+]

AUTHORS.md

@@ -1,187 +0,0 @@
-## Authors
-
-This file lists the people that have contributed to this project.
-
-Excluded from this list are @carols10cents and @diannasoreil, the principal
-authors.
-
-<!-- ALL-CONTRIBUTORS-LIST:START - Do not remove or modify this section -->
-<!-- prettier-ignore-start -->
-<!-- markdownlint-disable -->
-<table>
-  <tr>
-    <td align="center"><a href="http://carol-nichols.com"><img src="https://avatars2.githubusercontent.com/u/193874?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Carol (Nichols &#124;&#124; Goulding)</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=carols10cents" title="Code">💻</a> <a href="#content-carols10cents" title="Content">🖋</a></td>
-    <td align="center"><a href="https://twitter.com/QuietMisdreavus"><img src="https://avatars2.githubusercontent.com/u/5217170?v=4?s=100" width="100px;" alt=""/><br /><sub><b>QuietMisdreavus</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=QuietMisdreavus" title="Code">💻</a> <a href="#content-QuietMisdreavus" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/robertlugg"><img src="https://avatars0.githubusercontent.com/u/6054540?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Robert M Lugg</b></sub></a><br /><a href="#content-robertlugg" title="Content">🖋</a></td>
-    <td align="center"><a href="https://hynek.me/about/"><img src="https://avatars3.githubusercontent.com/u/41240?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Hynek Schlawack</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=hynek" title="Code">💻</a></td>
-    <td align="center"><a href="https://spacekookie.de"><img src="https://avatars0.githubusercontent.com/u/7669898?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Katharina Fey</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=spacekookie" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/lukabavdaz"><img src="https://avatars0.githubusercontent.com/u/9624558?v=4?s=100" width="100px;" alt=""/><br /><sub><b>lukabavdaz</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=lukabavdaz" title="Code">💻</a> <a href="#content-lukabavdaz" title="Content">🖋</a></td>
-    <td align="center"><a href="http://vestera.as"><img src="https://avatars2.githubusercontent.com/u/4187449?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Erik Vesteraas</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=evestera" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/Delet0r"><img src="https://avatars1.githubusercontent.com/u/23195618?v=4?s=100" width="100px;" alt=""/><br /><sub><b>delet0r</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=Delet0r" title="Code">💻</a></td>
-  </tr>
-  <tr>
-    <td align="center"><a href="http://phinary.ca"><img src="https://avatars1.githubusercontent.com/u/10522375?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Shaun Bennett</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=shaunbennett" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/abagshaw"><img src="https://avatars2.githubusercontent.com/u/8594541?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Andrew Bagshaw</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=abagshaw" title="Code">💻</a></td>
-    <td align="center"><a href="https://ai6ua.net/"><img src="https://avatars2.githubusercontent.com/u/175578?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Kyle Isom</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=kisom" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/ColinPitrat"><img src="https://avatars3.githubusercontent.com/u/1541863?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Colin Pitrat</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=ColinPitrat" title="Code">💻</a></td>
-    <td align="center"><a href="https://zacanger.com"><img src="https://avatars3.githubusercontent.com/u/12520493?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Zac Anger</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=zacanger" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/mgeier"><img src="https://avatars1.githubusercontent.com/u/705404?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Matthias Geier</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=mgeier" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/cjpearce"><img src="https://avatars1.githubusercontent.com/u/3453268?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Chris Pearce</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=cjpearce" title="Code">💻</a></td>
-    <td align="center"><a href="https://yvan-sraka.github.io"><img src="https://avatars2.githubusercontent.com/u/705213?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Yvan Sraka</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=yvan-sraka" title="Code">💻</a></td>
-  </tr>
-  <tr>
-    <td align="center"><a href="https://github.com/dendi239"><img src="https://avatars3.githubusercontent.com/u/16478650?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Denys Smirnov</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=dendi239" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/eddyp"><img src="https://avatars2.githubusercontent.com/u/123772?v=4?s=100" width="100px;" alt=""/><br /><sub><b>eddyp</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=eddyp" title="Code">💻</a></td>
-    <td align="center"><a href="http://about.me/BrianKung"><img src="https://avatars1.githubusercontent.com/u/2836167?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Brian Kung</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=briankung" title="Code">💻</a> <a href="#content-briankung" title="Content">🖋</a></td>
-    <td align="center"><a href="https://rcousineau.gitlab.io"><img src="https://avatars3.githubusercontent.com/u/281039?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Russell</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=miller-time" title="Code">💻</a></td>
-    <td align="center"><a href="http://danwilhelm.com"><img src="https://avatars3.githubusercontent.com/u/6137185?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Dan Wilhelm</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=danwilhelm" title="Documentation">📖</a></td>
-    <td align="center"><a href="https://github.com/Jesse-Cameron"><img src="https://avatars3.githubusercontent.com/u/3723654?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Jesse</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=Jesse-Cameron" title="Code">💻</a> <a href="#content-Jesse-Cameron" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/MrFroop"><img src="https://avatars3.githubusercontent.com/u/196700?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Fredrik Jambrén</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=MrFroop" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/petemcfarlane"><img src="https://avatars3.githubusercontent.com/u/3472717?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Pete McFarlane</b></sub></a><br /><a href="#content-petemcfarlane" title="Content">🖋</a></td>
-  </tr>
-  <tr>
-    <td align="center"><a href="https://github.com/nkanderson"><img src="https://avatars0.githubusercontent.com/u/4128825?v=4?s=100" width="100px;" alt=""/><br /><sub><b>nkanderson</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=nkanderson" title="Code">💻</a> <a href="#content-nkanderson" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/ajaxm"><img src="https://avatars0.githubusercontent.com/u/13360138?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Ajax M</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=ajaxm" title="Documentation">📖</a></td>
-    <td align="center"><a href="https://dylnuge.com"><img src="https://avatars2.githubusercontent.com/u/118624?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Dylan Nugent</b></sub></a><br /><a href="#content-Dylnuge" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/vyaslav"><img src="https://avatars0.githubusercontent.com/u/1385427?v=4?s=100" width="100px;" alt=""/><br /><sub><b>vyaslav</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=vyaslav" title="Code">💻</a> <a href="#content-vyaslav" title="Content">🖋</a></td>
-    <td align="center"><a href="https://join.sfxd.org"><img src="https://avatars1.githubusercontent.com/u/17297466?v=4?s=100" width="100px;" alt=""/><br /><sub><b>George</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=gdoenlen" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/nyxtom"><img src="https://avatars2.githubusercontent.com/u/222763?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Thomas Holloway</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=nyxtom" title="Code">💻</a> <a href="#content-nyxtom" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/workingjubilee"><img src="https://avatars1.githubusercontent.com/u/46493976?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Jubilee</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=workingjubilee" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/WofWca"><img src="https://avatars1.githubusercontent.com/u/39462442?v=4?s=100" width="100px;" alt=""/><br /><sub><b>WofWca</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=WofWca" title="Code">💻</a></td>
-  </tr>
-  <tr>
-    <td align="center"><a href="https://github.com/jrvidal"><img src="https://avatars0.githubusercontent.com/u/1636604?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Roberto Vidal</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=jrvidal" title="Code">💻</a> <a href="https://github.com/rust-lang/rustlings/commits?author=jrvidal" title="Documentation">📖</a> <a href="#ideas-jrvidal" title="Ideas, Planning, & Feedback">🤔</a> <a href="#maintenance-jrvidal" title="Maintenance">🚧</a></td>
-    <td align="center"><a href="https://github.com/jensim"><img src="https://avatars0.githubusercontent.com/u/3663856?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Jens</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=jensim" title="Documentation">📖</a></td>
-    <td align="center"><a href="http://rahatah.me/d"><img src="https://avatars3.githubusercontent.com/u/3174006?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Rahat Ahmed</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=rahatarmanahmed" title="Documentation">📖</a></td>
-    <td align="center"><a href="https://github.com/AbdouSeck"><img src="https://avatars2.githubusercontent.com/u/6490055?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Abdou Seck</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=AbdouSeck" title="Code">💻</a> <a href="#content-AbdouSeck" title="Content">🖋</a> <a href="https://github.com/rust-lang/rustlings/pulls?q=is%3Apr+reviewed-by%3AAbdouSeck" title="Reviewed Pull Requests">👀</a></td>
-    <td align="center"><a href="https://codehearts.com"><img src="https://avatars0.githubusercontent.com/u/2885412?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Katie</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=codehearts" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/Socratides"><img src="https://avatars3.githubusercontent.com/u/27732983?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Socrates</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=Socratides" title="Documentation">📖</a></td>
-    <td align="center"><a href="https://github.com/gnodarse"><img src="https://avatars3.githubusercontent.com/u/46761795?v=4?s=100" width="100px;" alt=""/><br /><sub><b>gnodarse</b></sub></a><br /><a href="#content-gnodarse" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/harrisonmetz"><img src="https://avatars1.githubusercontent.com/u/7883408?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Harrison Metzger</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=harrisonmetz" title="Code">💻</a></td>
-  </tr>
-  <tr>
-    <td align="center"><a href="https://github.com/TorbenJ"><img src="https://avatars2.githubusercontent.com/u/9077102?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Torben Jonas</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=TorbenJ" title="Code">💻</a> <a href="#content-TorbenJ" title="Content">🖋</a></td>
-    <td align="center"><a href="http://paulbissex.com/"><img src="https://avatars0.githubusercontent.com/u/641?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Paul Bissex</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=pbx" title="Documentation">📖</a></td>
-    <td align="center"><a href="https://github.com/sjmann"><img src="https://avatars0.githubusercontent.com/u/6589896?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Steven Mann</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=sjmann" title="Code">💻</a> <a href="#content-sjmann" title="Content">🖋</a></td>
-    <td align="center"><a href="https://smmdb.net/"><img src="https://avatars2.githubusercontent.com/u/5855071?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Mario Reder</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=Tarnadas" title="Code">💻</a> <a href="#content-Tarnadas" title="Content">🖋</a></td>
-    <td align="center"><a href="https://keybase.io/skim"><img src="https://avatars0.githubusercontent.com/u/47347?v=4?s=100" width="100px;" alt=""/><br /><sub><b>skim</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=sl4m" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/sanjaykdragon"><img src="https://avatars1.githubusercontent.com/u/10261698?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Sanjay K</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=sanjaykdragon" title="Code">💻</a> <a href="#content-sanjaykdragon" title="Content">🖋</a></td>
-    <td align="center"><a href="http://www.rohanjain.in"><img src="https://avatars1.githubusercontent.com/u/343499?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Rohan Jain</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=crodjer" title="Code">💻</a></td>
-    <td align="center"><a href="https://www.saidaspen.se"><img src="https://avatars1.githubusercontent.com/u/7727687?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Said Aspen</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=saidaspen" title="Code">💻</a> <a href="#content-saidaspen" title="Content">🖋</a></td>
-  </tr>
-  <tr>
-    <td align="center"><a href="https://github.com/uce"><img src="https://avatars3.githubusercontent.com/u/1756620?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Ufuk Celebi</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=uce" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/lebedevsergey"><img src="https://avatars2.githubusercontent.com/u/7325764?v=4?s=100" width="100px;" alt=""/><br /><sub><b>lebedevsergey</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=lebedevsergey" title="Documentation">📖</a></td>
-    <td align="center"><a href="https://github.com/avrong"><img src="https://avatars2.githubusercontent.com/u/6342851?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Aleksei Trifonov</b></sub></a><br /><a href="#content-avrong" title="Content">🖋</a></td>
-    <td align="center"><a href="https://drn.ie"><img src="https://avatars2.githubusercontent.com/u/411136?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Darren Meehan</b></sub></a><br /><a href="#content-Darrenmeehan" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/jihchi"><img src="https://avatars1.githubusercontent.com/u/87983?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Jihchi Lee</b></sub></a><br /><a href="#content-jihchi" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/bertonha"><img src="https://avatars3.githubusercontent.com/u/1225902?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Christofer Bertonha</b></sub></a><br /><a href="#content-bertonha" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/apatniv"><img src="https://avatars2.githubusercontent.com/u/22565917?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Vivek Bharath Akupatni</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=apatniv" title="Code">💻</a> <a href="https://github.com/rust-lang/rustlings/commits?author=apatniv" title="Tests">⚠️</a></td>
-    <td align="center"><a href="https://github.com/DiD92"><img src="https://avatars3.githubusercontent.com/u/6002416?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Dídac Sementé Fernández</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=DiD92" title="Code">💻</a> <a href="#content-DiD92" title="Content">🖋</a></td>
-  </tr>
-  <tr>
-    <td align="center"><a href="https://github.com/wrobstory"><img src="https://avatars3.githubusercontent.com/u/2601457?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Rob Story</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=wrobstory" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/siobhanjacobson"><img src="https://avatars2.githubusercontent.com/u/28983835?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Siobhan Jacobson</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=siobhanjacobson" title="Code">💻</a></td>
-    <td align="center"><a href="https://www.linkedin.com/in/evancarroll/"><img src="https://avatars2.githubusercontent.com/u/19922?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Evan Carroll</b></sub></a><br /><a href="#content-EvanCarroll" title="Content">🖋</a></td>
-    <td align="center"><a href="http://www.jawaadmahmood.com"><img src="https://avatars3.githubusercontent.com/u/95606?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Jawaad Mahmood</b></sub></a><br /><a href="#content-jmahmood" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/GaurangTandon"><img src="https://avatars1.githubusercontent.com/u/6308683?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Gaurang Tandon</b></sub></a><br /><a href="#content-GaurangTandon" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/dev-cyprium"><img src="https://avatars1.githubusercontent.com/u/6002628?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Stefan Kupresak</b></sub></a><br /><a href="#content-dev-cyprium" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/greg-el"><img src="https://avatars3.githubusercontent.com/u/45019882?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Greg Leonard</b></sub></a><br /><a href="#content-greg-el" title="Content">🖋</a></td>
-    <td align="center"><a href="https://ryanpcmcquen.org"><img src="https://avatars3.githubusercontent.com/u/772937?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Ryan McQuen</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=ryanpcmcquen" title="Code">💻</a></td>
-  </tr>
-  <tr>
-    <td align="center"><a href="https://github.com/AnnikaCodes"><img src="https://avatars3.githubusercontent.com/u/56906084?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Annika</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/pulls?q=is%3Apr+reviewed-by%3AAnnikaCodes" title="Reviewed Pull Requests">👀</a></td>
-    <td align="center"><a href="https://darnuria.eu"><img src="https://avatars1.githubusercontent.com/u/2827553?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Axel Viala</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=darnuria" title="Code">💻</a></td>
-    <td align="center"><a href="https://sazid.github.io"><img src="https://avatars1.githubusercontent.com/u/2370167?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Mohammed Sazid Al Rashid</b></sub></a><br /><a href="#content-sazid" title="Content">🖋</a> <a href="https://github.com/rust-lang/rustlings/commits?author=sazid" title="Code">💻</a></td>
-    <td align="center"><a href="https://codingthemsoftly.com"><img src="https://avatars1.githubusercontent.com/u/17479099?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Caleb Webber</b></sub></a><br /><a href="#maintenance-seeplusplus" title="Maintenance">🚧</a></td>
-    <td align="center"><a href="https://github.com/pcn"><img src="https://avatars2.githubusercontent.com/u/1056756?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Peter N</b></sub></a><br /><a href="#maintenance-pcn" title="Maintenance">🚧</a></td>
-    <td align="center"><a href="https://github.com/seancad"><img src="https://avatars1.githubusercontent.com/u/47405611?v=4?s=100" width="100px;" alt=""/><br /><sub><b>seancad</b></sub></a><br /><a href="#maintenance-seancad" title="Maintenance">🚧</a></td>
-    <td align="center"><a href="http://willhayworth.com"><img src="https://avatars3.githubusercontent.com/u/181174?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Will Hayworth</b></sub></a><br /><a href="#content-wsh" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/chrizel"><img src="https://avatars3.githubusercontent.com/u/20802?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Christian Zeller</b></sub></a><br /><a href="#content-chrizel" title="Content">🖋</a></td>
-  </tr>
-  <tr>
-    <td align="center"><a href="https://github.com/jfchevrette"><img src="https://avatars.githubusercontent.com/u/3001?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Jean-Francois Chevrette</b></sub></a><br /><a href="#content-jfchevrette" title="Content">🖋</a> <a href="https://github.com/rust-lang/rustlings/commits?author=jfchevrette" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/jbaber"><img src="https://avatars.githubusercontent.com/u/1908117?v=4?s=100" width="100px;" alt=""/><br /><sub><b>John Baber-Lucero</b></sub></a><br /><a href="#content-jbaber" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/tal-zvon"><img src="https://avatars.githubusercontent.com/u/3195851?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Tal</b></sub></a><br /><a href="#content-tal-zvon" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/apogeeoak"><img src="https://avatars.githubusercontent.com/u/59737221?v=4?s=100" width="100px;" alt=""/><br /><sub><b>apogeeoak</b></sub></a><br /><a href="#content-apogeeoak" title="Content">🖋</a> <a href="https://github.com/rust-lang/rustlings/commits?author=apogeeoak" title="Code">💻</a></td>
-    <td align="center"><a href="http://www.garfieldtech.com/"><img src="https://avatars.githubusercontent.com/u/254863?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Larry Garfield</b></sub></a><br /><a href="#content-Crell" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/circumspect"><img src="https://avatars.githubusercontent.com/u/40770208?v=4?s=100" width="100px;" alt=""/><br /><sub><b>circumspect</b></sub></a><br /><a href="#content-circumspect" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/cjwyett"><img src="https://avatars.githubusercontent.com/u/34195737?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Cyrus Wyett</b></sub></a><br /><a href="#content-cjwyett" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/cadolphs"><img src="https://avatars.githubusercontent.com/u/13894820?v=4?s=100" width="100px;" alt=""/><br /><sub><b>cadolphs</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=cadolphs" title="Code">💻</a></td>
-  </tr>
-  <tr>
-    <td align="center"><a href="https://www.haveneer.com"><img src="https://avatars.githubusercontent.com/u/26146722?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Pascal H.</b></sub></a><br /><a href="#content-hpwxf" title="Content">🖋</a></td>
-    <td align="center"><a href="https://twitter.com/chapeupreto"><img src="https://avatars.githubusercontent.com/u/834048?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Rod Elias</b></sub></a><br /><a href="#content-chapeupreto" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/blerchy"><img src="https://avatars.githubusercontent.com/u/2555355?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Matt Lebl</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=blerchy" title="Code">💻</a></td>
-    <td align="center"><a href="http://flakolefluk.dev"><img src="https://avatars.githubusercontent.com/u/11986564?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Ignacio Le Fluk</b></sub></a><br /><a href="#content-flakolefluk" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/tlyu"><img src="https://avatars.githubusercontent.com/u/431873?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Taylor Yu</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=tlyu" title="Code">💻</a> <a href="#content-tlyu" title="Content">🖋</a></td>
-    <td align="center"><a href="https://zerotask.github.io"><img src="https://avatars.githubusercontent.com/u/20150243?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Patrick Hintermayer</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=Zerotask" title="Code">💻</a></td>
-    <td align="center"><a href="https://petkopavlovski.com/"><img src="https://avatars.githubusercontent.com/u/32264020?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Pete Pavlovski</b></sub></a><br /><a href="#content-arthas168" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/k12ish"><img src="https://avatars.githubusercontent.com/u/45272873?v=4?s=100" width="100px;" alt=""/><br /><sub><b>k12ish</b></sub></a><br /><a href="#content-k12ish" title="Content">🖋</a></td>
-  </tr>
-  <tr>
-    <td align="center"><a href="https://github.com/hongshaoyang"><img src="https://avatars.githubusercontent.com/u/19281800?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Shao Yang Hong</b></sub></a><br /><a href="#content-hongshaoyang" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/bmacer"><img src="https://avatars.githubusercontent.com/u/13931806?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Brandon Macer</b></sub></a><br /><a href="#content-bmacer" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/stoiandan"><img src="https://avatars.githubusercontent.com/u/10388612?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Stoian Dan</b></sub></a><br /><a href="#content-stoiandan" title="Content">🖋</a></td>
-    <td align="center"><a href="https://about.me/pjdelport"><img src="https://avatars.githubusercontent.com/u/630271?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Pi Delport</b></sub></a><br /><a href="#content-PiDelport" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/sateeshkumarb"><img src="https://avatars.githubusercontent.com/u/429263?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Sateesh </b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=sateeshkumarb" title="Code">💻</a> <a href="#content-sateeshkumarb" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/kayuapi"><img src="https://avatars.githubusercontent.com/u/10304328?v=4?s=100" width="100px;" alt=""/><br /><sub><b>ZC</b></sub></a><br /><a href="#content-kayuapi" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/hyperparabolic"><img src="https://avatars.githubusercontent.com/u/12348474?v=4?s=100" width="100px;" alt=""/><br /><sub><b>hyperparabolic</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=hyperparabolic" title="Code">💻</a></td>
-    <td align="center"><a href="https://www.net4visions.at"><img src="https://avatars.githubusercontent.com/u/5228369?v=4?s=100" width="100px;" alt=""/><br /><sub><b>arlecchino</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=kolbma" title="Documentation">📖</a></td>
-  </tr>
-  <tr>
-    <td align="center"><a href="https://richthofen.io/"><img src="https://avatars.githubusercontent.com/u/7576730?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Richthofen</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=jazzplato" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/cseltol"><img src="https://avatars.githubusercontent.com/u/64264529?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Ivan Nerazumov</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=cseltol" title="Documentation">📖</a></td>
-    <td align="center"><a href="https://github.com/lauralindzey"><img src="https://avatars.githubusercontent.com/u/65185744?v=4?s=100" width="100px;" alt=""/><br /><sub><b>lauralindzey</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=lauralindzey" title="Documentation">📖</a></td>
-    <td align="center"><a href="https://github.com/sinharaksh1t"><img src="https://avatars.githubusercontent.com/u/28585848?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Rakshit Sinha</b></sub></a><br /><a href="#content-sinharaksh1t" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/dbednar230"><img src="https://avatars.githubusercontent.com/u/54457902?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Damian</b></sub></a><br /><a href="#content-dbednar230" title="Content">🖋</a></td>
-    <td align="center"><a href="https://benarmstead.co.uk"><img src="https://avatars.githubusercontent.com/u/70973680?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Ben Armstead</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=benarmstead" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/anuk909"><img src="https://avatars.githubusercontent.com/u/34924662?v=4?s=100" width="100px;" alt=""/><br /><sub><b>anuk909</b></sub></a><br /><a href="#content-anuk909" title="Content">🖋</a> <a href="https://github.com/rust-lang/rustlings/commits?author=anuk909" title="Code">💻</a></td>
-    <td align="center"><a href="https://granddaifuku.com/"><img src="https://avatars.githubusercontent.com/u/49578068?v=4?s=100" width="100px;" alt=""/><br /><sub><b>granddaifuku</b></sub></a><br /><a href="#content-granddaifuku" title="Content">🖋</a></td>
-  </tr>
-  <tr>
-    <td align="center"><a href="https://weilet.me"><img src="https://avatars.githubusercontent.com/u/32561597?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Weilet</b></sub></a><br /><a href="#content-Weilet" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/Millione"><img src="https://avatars.githubusercontent.com/u/38575932?v=4?s=100" width="100px;" alt=""/><br /><sub><b>LIU JIE</b></sub></a><br /><a href="#content-Millione" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/abusch"><img src="https://avatars.githubusercontent.com/u/506344?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Antoine Büsch</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=abusch" title="Code">💻</a></td>
-    <td align="center"><a href="https://frogtd.com/"><img src="https://avatars.githubusercontent.com/u/31412003?v=4?s=100" width="100px;" alt=""/><br /><sub><b>frogtd</b></sub></a><br /><a href="#content-frogtd" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/EmisonLu"><img src="https://avatars.githubusercontent.com/u/54395432?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Zhenghao Lu</b></sub></a><br /><a href="#content-EmisonLu" title="Content">🖋</a></td>
-    <td align="center"><a href="https://soundtrackyourbrand.com"><img src="https://avatars.githubusercontent.com/u/762956?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Fredrik Enestad</b></sub></a><br /><a href="#content-fredr" title="Content">🖋</a></td>
-    <td align="center"><a href="http://xuesong.pydevops.com"><img src="https://avatars.githubusercontent.com/u/18476085?v=4?s=100" width="100px;" alt=""/><br /><sub><b>xuesong</b></sub></a><br /><a href="#content-xuesongbj" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/MpdWalsh"><img src="https://avatars.githubusercontent.com/u/48160144?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Michael Walsh</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=MpdWalsh" title="Code">💻</a></td>
-  </tr>
-  <tr>
-    <td align="center"><a href="https://github.com/alirezaghey"><img src="https://avatars.githubusercontent.com/u/26653424?v=4?s=100" width="100px;" alt=""/><br /><sub><b>alirezaghey</b></sub></a><br /><a href="#content-alirezaghey" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/frvannes16"><img src="https://avatars.githubusercontent.com/u/3188475?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Franklin van Nes</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=frvannes16" title="Code">💻</a></td>
-    <td align="center"><a href="https://nekonako.github.io"><img src="https://avatars.githubusercontent.com/u/46141275?v=4?s=100" width="100px;" alt=""/><br /><sub><b>nekonako</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=nekonako" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/tan-zx"><img src="https://avatars.githubusercontent.com/u/67887489?v=4?s=100" width="100px;" alt=""/><br /><sub><b>ZX</b></sub></a><br /><a href="#content-tan-zx" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/sundevilyang"><img src="https://avatars.githubusercontent.com/u/1499214?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Yang Wen</b></sub></a><br /><a href="#content-sundevilyang" title="Content">🖋</a></td>
-    <td align="center"><a href="https://brandon-high.com"><img src="https://avatars.githubusercontent.com/u/759848?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Brandon High</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=highb" title="Documentation">📖</a></td>
-    <td align="center"><a href="https://github.com/x-hgg-x"><img src="https://avatars.githubusercontent.com/u/39058530?v=4?s=100" width="100px;" alt=""/><br /><sub><b>x-hgg-x</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=x-hgg-x" title="Code">💻</a></td>
-    <td align="center"><a href="http://kisaragieffective.github.io"><img src="https://avatars.githubusercontent.com/u/48310258?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Kisaragi</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=KisaragiEffective" title="Documentation">📖</a></td>
-  </tr>
-  <tr>
-    <td align="center"><a href="https://github.com/Kallu-A"><img src="https://avatars.githubusercontent.com/u/73198738?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Lucas Aries</b></sub></a><br /><a href="#content-Kallu-A" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/ragreenburg"><img src="https://avatars.githubusercontent.com/u/24358100?v=4?s=100" width="100px;" alt=""/><br /><sub><b>ragreenburg</b></sub></a><br /><a href="#content-ragreenburg" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/stevenfukase"><img src="https://avatars.githubusercontent.com/u/66785624?v=4?s=100" width="100px;" alt=""/><br /><sub><b>stevenfukase</b></sub></a><br /><a href="#content-stevenfukase" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/J-S-Kim"><img src="https://avatars.githubusercontent.com/u/17569303?v=4?s=100" width="100px;" alt=""/><br /><sub><b>J-S-Kim</b></sub></a><br /><a href="#content-J-S-Kim" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/Fointard"><img src="https://avatars.githubusercontent.com/u/9333398?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Fointard</b></sub></a><br /><a href="#content-Fointard" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/rytheo"><img src="https://avatars.githubusercontent.com/u/22184325?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Ryan Lowe</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=rytheo" title="Code">💻</a></td>
-    <td align="center"><a href="http://www.dashen.tech"><img src="https://avatars.githubusercontent.com/u/15921519?v=4?s=100" width="100px;" alt=""/><br /><sub><b>cui fliter</b></sub></a><br /><a href="#content-cuishuang" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/luskwater"><img src="https://avatars.githubusercontent.com/u/42529?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Ron Lusk</b></sub></a><br /><a href="#content-luskwater" title="Content">🖋</a></td>
-  </tr>
-  <tr>
-    <td align="center"><a href="http://liby.github.io/liby/"><img src="https://avatars.githubusercontent.com/u/38807139?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Bryan Lee</b></sub></a><br /><a href="#content-liby" title="Content">🖋</a></td>
-    <td align="center"><a href="http://nandaja.space"><img src="https://avatars.githubusercontent.com/u/2624550?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Nandaja Varma</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=nandajavarma" title="Documentation">📖</a></td>
-    <td align="center"><a href="https://github.com/merelymyself"><img src="https://avatars.githubusercontent.com/u/88221256?v=4?s=100" width="100px;" alt=""/><br /><sub><b>pwygab</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=merelymyself" title="Code">💻</a></td>
-    <td align="center"><a href="http://linkedin.com/in/lucasgrvarela"><img src="https://avatars.githubusercontent.com/u/37870368?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Lucas Grigolon Varela</b></sub></a><br /><a href="#content-lucasgrvarela" title="Content">🖋</a></td>
-    <td align="center"><a href="https://github.com/bufo24"><img src="https://avatars.githubusercontent.com/u/32884105?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Bufo</b></sub></a><br /><a href="#content-bufo24" title="Content">🖋</a></td>
-    <td align="center"><a href="http://rustnote.com"><img src="https://avatars.githubusercontent.com/u/77730378?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Jack Clayton</b></sub></a><br /><a href="https://github.com/rust-lang/rustlings/commits?author=jackos" title="Code">💻</a></td>
-  </tr>
-</table>
-
-<!-- markdownlint-restore -->
-<!-- prettier-ignore-end -->
-
-<!-- ALL-CONTRIBUTORS-LIST:END -->
-
-This project follows the [all-contributors](https://github.com/all-contributors/all-contributors) specification. Contributions of any kind welcome!

CONTRIBUTING.md

@@ -1,131 +1,61 @@
-## Contributing to Rustlings
+# Contributing to Rustlings
 
-First off, thanks for taking the time to contribute!! ❤️
+First off, thanks for taking the time to contribute! ❤️
 
-### Quick Reference
+## Quick Reference
 
-I want to...
+I want to …
 
-_add an exercise! ➡️ [read this](#addex) and then [open a Pull Request](#prs)_
+- _report a bug!_ ➡️ [open an issue](#issues)
+- _fix a bug!_ ➡️ [open a pull request](#pull-requests)
+- _implement a new feature!_ ➡️ [open an issue to discuss it first, then a pull request](#issues)
+- _add an exercise!_ ➡️ [read this](#adding-an-exercise)
+- _update an outdated exercise!_ ➡️ [open a pull request](#pull-requests)
 
-_update an outdated exercise! ➡️ [open a Pull Request](#prs)_
-
-_report a bug! ➡️ [open an Issue](#issues)_
-
-_fix a bug! ➡️ [open a Pull Request](#prs)_
-
-_implement a new feature! ➡️ [open an Issue to discuss it first, then a Pull Request](#issues)_
-
-<a name="#src"></a>
-### Working on the source code
-
-`rustlings` is basically a glorified `rustc` wrapper. Therefore the source code
-isn't really that complicated since the bulk of the work is done by `rustc`.
-`src/main.rs` contains a simple `clap` CLI that loads from `src/verify.rs` and `src/run.rs`.
-
-<a name="addex"></a>
-### Adding an exercise
-
-The first step is to add the exercise! Name the file `exercises/yourTopic/yourTopicN.rs`, make sure to
-put in some helpful links, and link to sections of the book in `exercises/yourTopic/README.md`.
-
-Next make sure it runs with `rustlings`. The exercise metadata is stored in `info.toml`, under the `exercises` array. The order of the `exercises` array determines the order the exercises are run by `rustlings verify`.
-
-Add the metadata for your exercise in the correct order in the `exercises` array. If you are unsure of the correct ordering, add it at the bottom and ask in your pull request. The exercise metadata should contain the following:
-```diff
-  ...
-+ [[exercises]]
-+ name = "yourTopicN"
-+ path = "exercises/yourTopic/yourTopicN.rs"
-+ mode = "compile"
-+ hint = """
-+ Some kind of useful hint for your exercise."""
-  ...
-```
-
-The `mode` attribute decides whether Rustlings will only compile your exercise, or compile and test it. If you have tests to verify in your exercise, choose `test`, otherwise `compile`.
-
-That's all! Feel free to put up a pull request.
-
-<a name="issues"></a>
-### Issues
+## Issues
 
 You can open an issue [here](https://github.com/rust-lang/rustlings/issues/new).
 If you're reporting a bug, please include the output of the following commands:
 
-- `rustc --version`
+- `cargo --version`
 - `rustlings --version`
 - `ls -la`
 - Your OS name and version
 
-<a name="prs"></a>
-### Pull Requests
+## Pull Requests
 
-Opening a pull request is as easy as forking the repository and committing your
-changes. There's a couple of things to watch out for:
+You are welcome to open a pull request, but unless it is small and trivial, **please open an issue to discuss your idea first** 🙏🏼
 
-#### Write correct commit messages
+Opening a pull request is as easy as forking the repository and committing your changes.
+If you need any help with it or face any Git related problems, don't hesitate to ask for help 🤗
 
-We follow the [Conventional Commits](https://www.conventionalcommits.org/en/v1.0.0-beta.4/)
-specification, because it makes it easier to generate changelogs automatically.
-This means that you have to format your commit messages in a specific way. Say
-you're working on adding a new exercise called `foobar1.rs`. You could write
-the following commit message:
+It may take time to review your pull request.
+Please be patient 😇
 
-```
-feat: Add foobar1.rs exercise
+When updating an exercise, check if its solution needs to be updated.
+
+## Adding An Exercise
+
+- Name the file `exercises/yourTopic/yourTopicN.rs`.
+- Make sure to put in some helpful links, and link to sections of The Book in `exercises/yourTopic/README.md`.
+- In the exercise, add a `// TODO: …` comment where user changes are required.
+- Add a solution at `solutions/yourTopic/yourTopicN.rs` with comments explaining it.
+- Add the [metadata for your exercise](#exercise-metadata) in the `rustlings-macros/info.toml` file.
+- Make sure your exercise runs with `rustlings run yourTopicN`.
+- [Open a pull request](#pull-requests).
+
+### Exercise Metadata
+
+The exercise metadata should contain the following:
+
+```toml
+[[exercises]]
+name = "yourTopicN"
+dir = "yourTopic"
+hint = """
+A useful (multi-line) hint for your exercise.
+Include links to a section in The Book or a documentation page."""
 ```
 
-If you're just fixing a bug, please use the `fix` type:
-
-```
-fix(verify): Make sure verify doesn't self-destruct
-```
-
-The scope within the brackets is optional, but should be any of these:
-
-- `installation` (for the installation script)
-- `cli` (for general CLI changes)
-- `verify` (for the verification source file)
-- `watch` (for the watch functionality source)
-- `run` (for the run functionality source)
-- `EXERCISENAME` (if you're changing a specific exercise, or set of exercises,
-  substitute them here)
-
-When the commit also happens to close an existing issue, link it in the message
-body:
-
-```
-fix: Update foobar
-
-closes #101029908
-```
-
-If you're doing simple changes, like updating a book link, use `chore`:
-
-```
-chore: Update exercise1.rs book link
-```
-
-If you're updating documentation, use `docs`:
-
-```
-docs: Add more information to Readme
-```
-
-If, and only if, you're absolutely sure you want to make a breaking change
-(please discuss this beforehand!), add an exclamation mark to the type and
-explain the breaking change in the message body:
-
-```
-fix!: Completely change verification
-
-BREAKING CHANGE: This has to be done because lorem ipsum dolor
-```
-
-#### Pull Request Workflow
-
-Once you open a Pull Request, it may be reviewed or labeled (or both) until
-the maintainers accept your change. Then, [bors](https://github.com/bors) will
-run the test suite with your changes and if it's successful, automatically
-merge it in!
+If your exercise doesn't contain any test, add `test = false` to the exercise metadata.
+But adding tests is recommended.

Cargo.toml

@@ -1,29 +1,88 @@
+[workspace]
+resolver = "2"
+exclude = [
+  "tests/test_exercises",
+  "dev",
+]
+
+[workspace.package]
+version = "6.4.0"
+authors = [
+  "Mo Bitar <mo8it@proton.me>", # https://github.com/mo8it
+  "Liv <mokou@fastmail.com>", # https://github.com/shadows-withal
+  # Alumni
+  "Carol (Nichols || Goulding) <carol.nichols@gmail.com>", # https://github.com/carols10cents
+]
+repository = "https://github.com/rust-lang/rustlings"
+license = "MIT"
+edition = "2024" # On Update: Update the edition of `rustfmt` in `dev check` and `CARGO_TOML` in `dev new`.
+rust-version = "1.87"
+
+[workspace.dependencies]
+serde = { version = "1.0", features = ["derive"] }
+toml_edit = { version = "0.22", default-features = false, features = ["parse", "serde"] }
+
 [package]
 name = "rustlings"
-version = "4.8.0"
-authors = ["mokou <mokou@fastmail.com>", "Carol (Nichols || Goulding) <carol.nichols@gmail.com>"]
-edition = "2021"
+description = "Small exercises to get you used to reading and writing Rust code!"
+version.workspace = true
+authors.workspace = true
+repository.workspace = true
+license.workspace = true
+edition.workspace = true
+rust-version.workspace = true
+keywords = [
+  "exercise",
+  "learning",
+]
+include = [
+  "/src/",
+  "/exercises/",
+  "/solutions/",
+  # A symlink to be able to include `dev/Cargo.toml` although `dev` is excluded.
+  "/dev-Cargo.toml",
+  "/README.md",
+  "/LICENSE",
+]
 
 [dependencies]
-argh = "0.1"
-indicatif = "0.16"
-console = "0.15"
-notify = "4.0"
-toml = "0.5"
-regex = "1.5"
-serde= { version = "1.0", features = ["derive"] }
-serde_json = "1.0.81"
-home = "0.5.3"
-glob = "0.3.0"
+anyhow = "1.0"
+clap = { version = "4.5", features = ["derive"] }
+crossterm = { version = "0.29", default-features = false, features = ["windows", "events"] }
+notify = "8.0"
+rustlings-macros = { path = "rustlings-macros", version = "=6.4.0" }
+serde_json = "1.0"
+serde.workspace = true
+toml_edit.workspace = true
 
-[[bin]]
-name = "rustlings"
-path = "src/main.rs"
+[target.'cfg(not(windows))'.dependencies]
+rustix = { version = "1.0", default-features = false, features = ["std", "stdio", "termios"] }
 
 [dev-dependencies]
-assert_cmd = "0.11.0"
-predicates = "1.0.1"
-glob = "0.3.0"
+tempfile = "3.19"
 
-[features]
-exercises = []
+[profile.release]
+panic = "abort"
+
+[profile.dev]
+panic = "abort"
+
+[package.metadata.release]
+pre-release-hook = ["./release-hook.sh"]
+pre-release-commit-message = "Release 🎉"
+
+[workspace.lints.rust]
+unsafe_code = "forbid"
+unstable_features = "forbid"
+
+[workspace.lints.clippy]
+empty_loop = "forbid"
+disallowed-types = "deny"
+disallowed-methods = "deny"
+infinite_loop = "deny"
+mem_forget = "deny"
+dbg_macro = "warn"
+todo = "warn"
+
+[lints]
+workspace = true

README.md

@@ -1,177 +1,7 @@
-# rustlings 🦀❤️
+# [Rustlings](https://rustlings.rust-lang.org) 🦀
 
-Greetings and welcome to `rustlings`. This project contains small exercises to get you used to reading and writing Rust code. This includes reading and responding to compiler messages!
+Small exercises to get you used to reading and writing [Rust](https://www.rust-lang.org) code - _Recommended in parallel to reading [the official Rust book](https://doc.rust-lang.org/book) 📚️_
 
-_...looking for the old, web-based version of Rustlings? Try [here](https://github.com/rust-lang/rustlings/tree/rustlings-1)_
+Visit the **website** for a demo, info about setup and more:
 
-Alternatively, for a first-time Rust learner, there are several other resources:
-
-- [The Book](https://doc.rust-lang.org/book/index.html) - The most comprehensive resource for learning Rust, but a bit theoretical sometimes. You will be using this along with Rustlings!
-- [Rust By Example](https://doc.rust-lang.org/rust-by-example/index.html) - Learn Rust by solving little exercises! It's almost like `rustlings`, but online
-
-## Getting Started
-
-_Note: If you're on MacOS, make sure you've installed Xcode and its developer tools by typing `xcode-select --install`._
-_Note: If you're on Linux, make sure you've installed gcc. Deb: `sudo apt install gcc`. Yum: `sudo yum -y install gcc`._
-
-You will need to have Rust installed. You can get it by visiting https://rustup.rs. This'll also install Cargo, Rust's package/project manager.
-
-## MacOS/Linux
-
-Just run:
-
-```bash
-curl -L https://raw.githubusercontent.com/rust-lang/rustlings/main/install.sh | bash
-# Or if you want it to be installed to a different path:
-curl -L https://raw.githubusercontent.com/rust-lang/rustlings/main/install.sh | bash -s mypath/
-```
-
-This will install Rustlings and give you access to the `rustlings` command. Run it to get started!
-
-## Windows
-
-In PowerShell (Run as Administrator), set `ExecutionPolicy` to `RemoteSigned`:
-
-```ps1
-Set-ExecutionPolicy -ExecutionPolicy RemoteSigned -Scope CurrentUser
-```
-
-Then, you can run:
-
-```ps1
-Start-BitsTransfer -Source https://raw.githubusercontent.com/rust-lang/rustlings/main/install.ps1 -Destination $env:TMP/install_rustlings.ps1; Unblock-File $env:TMP/install_rustlings.ps1; Invoke-Expression $env:TMP/install_rustlings.ps1
-```
-
-To install Rustlings. Same as on MacOS/Linux, you will have access to the `rustlings` command after it.
-
-When you get a permission denied message then you have to exclude the directory where you placed the rustlings in your virus-scanner
-
-## Browser:
-
-[Run on Repl.it](https://repl.it/github/rust-lang/rustlings)
-
-[![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/#https://github.com/rust-lang/rustlings)
-
-## Manually
-
-Basically: Clone the repository at the latest tag, run `cargo install`.
-
-```bash
-# find out the latest version at https://github.com/rust-lang/rustlings/releases/latest (on edit 4.7.1)
-git clone -b 4.7.1 --depth 1 https://github.com/rust-lang/rustlings
-cd rustlings
-cargo install --force --path .
-```
-
-If there are installation errors, ensure that your toolchain is up to date. For the latest, run:
-
-```bash
-rustup update
-```
-
-Then, same as above, run `rustlings` to get started.
-
-## Doing exercises
-
-The exercises are sorted by topic and can be found in the subdirectory `rustlings/exercises/<topic>`. For every topic there is an additional README file with some resources to get you started on the topic. We really recommend that you have a look at them before you start.
-
-The task is simple. Most exercises contain an error that keeps them from compiling, and it's up to you to fix it! Some exercises are also run as tests, but rustlings handles them all the same. To run the exercises in the recommended order, execute:
-
-```bash
-rustlings watch
-```
-
-This will try to verify the completion of every exercise in a predetermined order (what we think is best for newcomers). It will also rerun automatically every time you change a file in the `exercises/` directory. If you want to only run it once, you can use:
-
-```bash
-rustlings verify
-```
-
-This will do the same as watch, but it'll quit after running.
-
-In case you want to go by your own order, or want to only verify a single exercise, you can run:
-
-```bash
-rustlings run myExercise1
-```
-
-Or simply use the following command to run the next unsolved exercise in the course:
-
-```bash
-rustlings run next
-```
-
-In case you get stuck, you can run the following command to get a hint for your
-exercise:
-
-```bash
-rustlings hint myExercise1
-```
-
-You can also get the hint for the next unsolved exercise with the following command:
-
-```bash
-rustlings hint next
-```
-
-To check your progress, you can run the following command:
-
-```bash
-rustlings list
-```
-
-## Testing yourself
-
-After every couple of sections, there will be a quiz that'll test your knowledge on a bunch of sections at once. These quizzes are found in `exercises/quizN.rs`.
-
-## Enabling `rust-analyzer`
-
-Run the command `rustlings lsp` which will generate a `rust-project.json` at the root of the project, this allows [rust-analyzer](https://rust-analyzer.github.io/) to parse each exercise. 
-
-## Continuing On
-
-Once you've completed Rustlings, put your new knowledge to good use! Continue practicing your Rust skills by building your own projects, contributing to Rustlings, or finding other open-source projects to contribute to.
-
-## Uninstalling Rustlings
-
-If you want to remove Rustlings from your system, there's two steps. First, you'll need to remove the exercises folder that the install script created
-for you:
-
-```bash
-rm -rf rustlings # or your custom folder name, if you chose and or renamed it
-```
-
-Second, since Rustlings got installed via `cargo install`, it's only reasonable to assume that you can also remove it using Cargo, and
-exactly that is the case. Run `cargo uninstall` to remove the `rustlings` binary:
-
-```bash
-cargo uninstall rustlings
-```
-
-Now you should be done!
-
-## Completion
-
-Rustlings isn't done; there are a couple of sections that are very experimental and don't have proper documentation. These include:
-
-- Errors (`exercises/errors/`)
-- Option (`exercises/option/`)
-- Result (`exercises/result/`)
-- Move Semantics (could still be improved, `exercises/move_semantics/`)
-
-Additionally, we could use exercises on a couple of topics:
-
-- Structs
-- Better ownership stuff
-- `impl`
-- ??? probably more
-
-If you are interested in improving or adding new ones, please feel free to contribute! Read on for more information :)
-
-## Contributing
-
-See [CONTRIBUTING.md](./CONTRIBUTING.md).
-
-## Contributors ✨
-
-Thanks goes to the wonderful people listed in [AUTHORS.md](./AUTHORS.md) 🎉
+## ➡️ [rustlings.rust-lang.org](https://rustlings.rust-lang.org) ⬅️

build.rs

@@ -0,0 +1,5 @@
+fn main() {
+    // Fix building from source on Windows because it can't handle file links.
+    #[cfg(windows)]
+    let _ = std::fs::copy("dev/Cargo.toml", "dev-Cargo.toml");
+}

clippy.toml

@@ -0,0 +1,15 @@
+disallowed-types = [
+  # Inefficient. Use `.queue(…)` instead.
+  "crossterm::style::Stylize",
+  "crossterm::style::styled_content::StyledContent",
+]
+
+disallowed-methods = [
+  # Inefficient. Use `.queue(…)` instead.
+  "crossterm::style::style",
+  # Use `thread::Builder::spawn` instead and handle the error.
+  "std::thread::spawn",
+  "std::thread::Scope::spawn",
+  # Return `ExitCode` instead.
+  "std::process::exit",
+]

dev-Cargo.toml

@@ -0,0 +1 @@
+dev/Cargo.toml

dev/Cargo.toml

@@ -0,0 +1,223 @@
+# Don't edit the `bin` list manually! It is updated by `cargo dev update`. This comment line will be stripped in `rustlings init`.
+bin = [
+  { name = "intro1", path = "../exercises/00_intro/intro1.rs" },
+  { name = "intro1_sol", path = "../solutions/00_intro/intro1.rs" },
+  { name = "intro2", path = "../exercises/00_intro/intro2.rs" },
+  { name = "intro2_sol", path = "../solutions/00_intro/intro2.rs" },
+  { name = "variables1", path = "../exercises/01_variables/variables1.rs" },
+  { name = "variables1_sol", path = "../solutions/01_variables/variables1.rs" },
+  { name = "variables2", path = "../exercises/01_variables/variables2.rs" },
+  { name = "variables2_sol", path = "../solutions/01_variables/variables2.rs" },
+  { name = "variables3", path = "../exercises/01_variables/variables3.rs" },
+  { name = "variables3_sol", path = "../solutions/01_variables/variables3.rs" },
+  { name = "variables4", path = "../exercises/01_variables/variables4.rs" },
+  { name = "variables4_sol", path = "../solutions/01_variables/variables4.rs" },
+  { name = "variables5", path = "../exercises/01_variables/variables5.rs" },
+  { name = "variables5_sol", path = "../solutions/01_variables/variables5.rs" },
+  { name = "variables6", path = "../exercises/01_variables/variables6.rs" },
+  { name = "variables6_sol", path = "../solutions/01_variables/variables6.rs" },
+  { name = "functions1", path = "../exercises/02_functions/functions1.rs" },
+  { name = "functions1_sol", path = "../solutions/02_functions/functions1.rs" },
+  { name = "functions2", path = "../exercises/02_functions/functions2.rs" },
+  { name = "functions2_sol", path = "../solutions/02_functions/functions2.rs" },
+  { name = "functions3", path = "../exercises/02_functions/functions3.rs" },
+  { name = "functions3_sol", path = "../solutions/02_functions/functions3.rs" },
+  { name = "functions4", path = "../exercises/02_functions/functions4.rs" },
+  { name = "functions4_sol", path = "../solutions/02_functions/functions4.rs" },
+  { name = "functions5", path = "../exercises/02_functions/functions5.rs" },
+  { name = "functions5_sol", path = "../solutions/02_functions/functions5.rs" },
+  { name = "if1", path = "../exercises/03_if/if1.rs" },
+  { name = "if1_sol", path = "../solutions/03_if/if1.rs" },
+  { name = "if2", path = "../exercises/03_if/if2.rs" },
+  { name = "if2_sol", path = "../solutions/03_if/if2.rs" },
+  { name = "if3", path = "../exercises/03_if/if3.rs" },
+  { name = "if3_sol", path = "../solutions/03_if/if3.rs" },
+  { name = "quiz1", path = "../exercises/quizzes/quiz1.rs" },
+  { name = "quiz1_sol", path = "../solutions/quizzes/quiz1.rs" },
+  { name = "primitive_types1", path = "../exercises/04_primitive_types/primitive_types1.rs" },
+  { name = "primitive_types1_sol", path = "../solutions/04_primitive_types/primitive_types1.rs" },
+  { name = "primitive_types2", path = "../exercises/04_primitive_types/primitive_types2.rs" },
+  { name = "primitive_types2_sol", path = "../solutions/04_primitive_types/primitive_types2.rs" },
+  { name = "primitive_types3", path = "../exercises/04_primitive_types/primitive_types3.rs" },
+  { name = "primitive_types3_sol", path = "../solutions/04_primitive_types/primitive_types3.rs" },
+  { name = "primitive_types4", path = "../exercises/04_primitive_types/primitive_types4.rs" },
+  { name = "primitive_types4_sol", path = "../solutions/04_primitive_types/primitive_types4.rs" },
+  { name = "primitive_types5", path = "../exercises/04_primitive_types/primitive_types5.rs" },
+  { name = "primitive_types5_sol", path = "../solutions/04_primitive_types/primitive_types5.rs" },
+  { name = "primitive_types6", path = "../exercises/04_primitive_types/primitive_types6.rs" },
+  { name = "primitive_types6_sol", path = "../solutions/04_primitive_types/primitive_types6.rs" },
+  { name = "vecs1", path = "../exercises/05_vecs/vecs1.rs" },
+  { name = "vecs1_sol", path = "../solutions/05_vecs/vecs1.rs" },
+  { name = "vecs2", path = "../exercises/05_vecs/vecs2.rs" },
+  { name = "vecs2_sol", path = "../solutions/05_vecs/vecs2.rs" },
+  { name = "move_semantics1", path = "../exercises/06_move_semantics/move_semantics1.rs" },
+  { name = "move_semantics1_sol", path = "../solutions/06_move_semantics/move_semantics1.rs" },
+  { name = "move_semantics2", path = "../exercises/06_move_semantics/move_semantics2.rs" },
+  { name = "move_semantics2_sol", path = "../solutions/06_move_semantics/move_semantics2.rs" },
+  { name = "move_semantics3", path = "../exercises/06_move_semantics/move_semantics3.rs" },
+  { name = "move_semantics3_sol", path = "../solutions/06_move_semantics/move_semantics3.rs" },
+  { name = "move_semantics4", path = "../exercises/06_move_semantics/move_semantics4.rs" },
+  { name = "move_semantics4_sol", path = "../solutions/06_move_semantics/move_semantics4.rs" },
+  { name = "move_semantics5", path = "../exercises/06_move_semantics/move_semantics5.rs" },
+  { name = "move_semantics5_sol", path = "../solutions/06_move_semantics/move_semantics5.rs" },
+  { name = "structs1", path = "../exercises/07_structs/structs1.rs" },
+  { name = "structs1_sol", path = "../solutions/07_structs/structs1.rs" },
+  { name = "structs2", path = "../exercises/07_structs/structs2.rs" },
+  { name = "structs2_sol", path = "../solutions/07_structs/structs2.rs" },
+  { name = "structs3", path = "../exercises/07_structs/structs3.rs" },
+  { name = "structs3_sol", path = "../solutions/07_structs/structs3.rs" },
+  { name = "enums1", path = "../exercises/08_enums/enums1.rs" },
+  { name = "enums1_sol", path = "../solutions/08_enums/enums1.rs" },
+  { name = "enums2", path = "../exercises/08_enums/enums2.rs" },
+  { name = "enums2_sol", path = "../solutions/08_enums/enums2.rs" },
+  { name = "enums3", path = "../exercises/08_enums/enums3.rs" },
+  { name = "enums3_sol", path = "../solutions/08_enums/enums3.rs" },
+  { name = "strings1", path = "../exercises/09_strings/strings1.rs" },
+  { name = "strings1_sol", path = "../solutions/09_strings/strings1.rs" },
+  { name = "strings2", path = "../exercises/09_strings/strings2.rs" },
+  { name = "strings2_sol", path = "../solutions/09_strings/strings2.rs" },
+  { name = "strings3", path = "../exercises/09_strings/strings3.rs" },
+  { name = "strings3_sol", path = "../solutions/09_strings/strings3.rs" },
+  { name = "strings4", path = "../exercises/09_strings/strings4.rs" },
+  { name = "strings4_sol", path = "../solutions/09_strings/strings4.rs" },
+  { name = "modules1", path = "../exercises/10_modules/modules1.rs" },
+  { name = "modules1_sol", path = "../solutions/10_modules/modules1.rs" },
+  { name = "modules2", path = "../exercises/10_modules/modules2.rs" },
+  { name = "modules2_sol", path = "../solutions/10_modules/modules2.rs" },
+  { name = "modules3", path = "../exercises/10_modules/modules3.rs" },
+  { name = "modules3_sol", path = "../solutions/10_modules/modules3.rs" },
+  { name = "hashmaps1", path = "../exercises/11_hashmaps/hashmaps1.rs" },
+  { name = "hashmaps1_sol", path = "../solutions/11_hashmaps/hashmaps1.rs" },
+  { name = "hashmaps2", path = "../exercises/11_hashmaps/hashmaps2.rs" },
+  { name = "hashmaps2_sol", path = "../solutions/11_hashmaps/hashmaps2.rs" },
+  { name = "hashmaps3", path = "../exercises/11_hashmaps/hashmaps3.rs" },
+  { name = "hashmaps3_sol", path = "../solutions/11_hashmaps/hashmaps3.rs" },
+  { name = "quiz2", path = "../exercises/quizzes/quiz2.rs" },
+  { name = "quiz2_sol", path = "../solutions/quizzes/quiz2.rs" },
+  { name = "options1", path = "../exercises/12_options/options1.rs" },
+  { name = "options1_sol", path = "../solutions/12_options/options1.rs" },
+  { name = "options2", path = "../exercises/12_options/options2.rs" },
+  { name = "options2_sol", path = "../solutions/12_options/options2.rs" },
+  { name = "options3", path = "../exercises/12_options/options3.rs" },
+  { name = "options3_sol", path = "../solutions/12_options/options3.rs" },
+  { name = "errors1", path = "../exercises/13_error_handling/errors1.rs" },
+  { name = "errors1_sol", path = "../solutions/13_error_handling/errors1.rs" },
+  { name = "errors2", path = "../exercises/13_error_handling/errors2.rs" },
+  { name = "errors2_sol", path = "../solutions/13_error_handling/errors2.rs" },
+  { name = "errors3", path = "../exercises/13_error_handling/errors3.rs" },
+  { name = "errors3_sol", path = "../solutions/13_error_handling/errors3.rs" },
+  { name = "errors4", path = "../exercises/13_error_handling/errors4.rs" },
+  { name = "errors4_sol", path = "../solutions/13_error_handling/errors4.rs" },
+  { name = "errors5", path = "../exercises/13_error_handling/errors5.rs" },
+  { name = "errors5_sol", path = "../solutions/13_error_handling/errors5.rs" },
+  { name = "errors6", path = "../exercises/13_error_handling/errors6.rs" },
+  { name = "errors6_sol", path = "../solutions/13_error_handling/errors6.rs" },
+  { name = "generics1", path = "../exercises/14_generics/generics1.rs" },
+  { name = "generics1_sol", path = "../solutions/14_generics/generics1.rs" },
+  { name = "generics2", path = "../exercises/14_generics/generics2.rs" },
+  { name = "generics2_sol", path = "../solutions/14_generics/generics2.rs" },
+  { name = "traits1", path = "../exercises/15_traits/traits1.rs" },
+  { name = "traits1_sol", path = "../solutions/15_traits/traits1.rs" },
+  { name = "traits2", path = "../exercises/15_traits/traits2.rs" },
+  { name = "traits2_sol", path = "../solutions/15_traits/traits2.rs" },
+  { name = "traits3", path = "../exercises/15_traits/traits3.rs" },
+  { name = "traits3_sol", path = "../solutions/15_traits/traits3.rs" },
+  { name = "traits4", path = "../exercises/15_traits/traits4.rs" },
+  { name = "traits4_sol", path = "../solutions/15_traits/traits4.rs" },
+  { name = "traits5", path = "../exercises/15_traits/traits5.rs" },
+  { name = "traits5_sol", path = "../solutions/15_traits/traits5.rs" },
+  { name = "quiz3", path = "../exercises/quizzes/quiz3.rs" },
+  { name = "quiz3_sol", path = "../solutions/quizzes/quiz3.rs" },
+  { name = "lifetimes1", path = "../exercises/16_lifetimes/lifetimes1.rs" },
+  { name = "lifetimes1_sol", path = "../solutions/16_lifetimes/lifetimes1.rs" },
+  { name = "lifetimes2", path = "../exercises/16_lifetimes/lifetimes2.rs" },
+  { name = "lifetimes2_sol", path = "../solutions/16_lifetimes/lifetimes2.rs" },
+  { name = "lifetimes3", path = "../exercises/16_lifetimes/lifetimes3.rs" },
+  { name = "lifetimes3_sol", path = "../solutions/16_lifetimes/lifetimes3.rs" },
+  { name = "tests1", path = "../exercises/17_tests/tests1.rs" },
+  { name = "tests1_sol", path = "../solutions/17_tests/tests1.rs" },
+  { name = "tests2", path = "../exercises/17_tests/tests2.rs" },
+  { name = "tests2_sol", path = "../solutions/17_tests/tests2.rs" },
+  { name = "tests3", path = "../exercises/17_tests/tests3.rs" },
+  { name = "tests3_sol", path = "../solutions/17_tests/tests3.rs" },
+  { name = "iterators1", path = "../exercises/18_iterators/iterators1.rs" },
+  { name = "iterators1_sol", path = "../solutions/18_iterators/iterators1.rs" },
+  { name = "iterators2", path = "../exercises/18_iterators/iterators2.rs" },
+  { name = "iterators2_sol", path = "../solutions/18_iterators/iterators2.rs" },
+  { name = "iterators3", path = "../exercises/18_iterators/iterators3.rs" },
+  { name = "iterators3_sol", path = "../solutions/18_iterators/iterators3.rs" },
+  { name = "iterators4", path = "../exercises/18_iterators/iterators4.rs" },
+  { name = "iterators4_sol", path = "../solutions/18_iterators/iterators4.rs" },
+  { name = "iterators5", path = "../exercises/18_iterators/iterators5.rs" },
+  { name = "iterators5_sol", path = "../solutions/18_iterators/iterators5.rs" },
+  { name = "box1", path = "../exercises/19_smart_pointers/box1.rs" },
+  { name = "box1_sol", path = "../solutions/19_smart_pointers/box1.rs" },
+  { name = "rc1", path = "../exercises/19_smart_pointers/rc1.rs" },
+  { name = "rc1_sol", path = "../solutions/19_smart_pointers/rc1.rs" },
+  { name = "arc1", path = "../exercises/19_smart_pointers/arc1.rs" },
+  { name = "arc1_sol", path = "../solutions/19_smart_pointers/arc1.rs" },
+  { name = "cow1", path = "../exercises/19_smart_pointers/cow1.rs" },
+  { name = "cow1_sol", path = "../solutions/19_smart_pointers/cow1.rs" },
+  { name = "threads1", path = "../exercises/20_threads/threads1.rs" },
+  { name = "threads1_sol", path = "../solutions/20_threads/threads1.rs" },
+  { name = "threads2", path = "../exercises/20_threads/threads2.rs" },
+  { name = "threads2_sol", path = "../solutions/20_threads/threads2.rs" },
+  { name = "threads3", path = "../exercises/20_threads/threads3.rs" },
+  { name = "threads3_sol", path = "../solutions/20_threads/threads3.rs" },
+  { name = "macros1", path = "../exercises/21_macros/macros1.rs" },
+  { name = "macros1_sol", path = "../solutions/21_macros/macros1.rs" },
+  { name = "macros2", path = "../exercises/21_macros/macros2.rs" },
+  { name = "macros2_sol", path = "../solutions/21_macros/macros2.rs" },
+  { name = "macros3", path = "../exercises/21_macros/macros3.rs" },
+  { name = "macros3_sol", path = "../solutions/21_macros/macros3.rs" },
+  { name = "macros4", path = "../exercises/21_macros/macros4.rs" },
+  { name = "macros4_sol", path = "../solutions/21_macros/macros4.rs" },
+  { name = "clippy1", path = "../exercises/22_clippy/clippy1.rs" },
+  { name = "clippy1_sol", path = "../solutions/22_clippy/clippy1.rs" },
+  { name = "clippy2", path = "../exercises/22_clippy/clippy2.rs" },
+  { name = "clippy2_sol", path = "../solutions/22_clippy/clippy2.rs" },
+  { name = "clippy3", path = "../exercises/22_clippy/clippy3.rs" },
+  { name = "clippy3_sol", path = "../solutions/22_clippy/clippy3.rs" },
+  { name = "using_as", path = "../exercises/23_conversions/using_as.rs" },
+  { name = "using_as_sol", path = "../solutions/23_conversions/using_as.rs" },
+  { name = "from_into", path = "../exercises/23_conversions/from_into.rs" },
+  { name = "from_into_sol", path = "../solutions/23_conversions/from_into.rs" },
+  { name = "from_str", path = "../exercises/23_conversions/from_str.rs" },
+  { name = "from_str_sol", path = "../solutions/23_conversions/from_str.rs" },
+  { name = "try_from_into", path = "../exercises/23_conversions/try_from_into.rs" },
+  { name = "try_from_into_sol", path = "../solutions/23_conversions/try_from_into.rs" },
+  { name = "as_ref_mut", path = "../exercises/23_conversions/as_ref_mut.rs" },
+  { name = "as_ref_mut_sol", path = "../solutions/23_conversions/as_ref_mut.rs" },
+]
+
+[package]
+name = "exercises"
+edition = "2024"
+# Don't publish the exercises on crates.io!
+publish = false
+
+[profile.release]
+panic = "abort"
+
+[profile.dev]
+panic = "abort"
+
+[lints.rust]
+# You shouldn't write unsafe code in Rustlings!
+unsafe_code = "forbid"
+# You don't need unstable features in Rustlings and shouldn't rely on them while learning Rust.
+unstable_features = "forbid"
+# Dead code warnings can't be avoided in some exercises and might distract while learning.
+dead_code = "allow"
+
+[lints.clippy]
+# You forgot a `todo!()`!
+todo = "forbid"
+# This can only happen by mistake in Rustlings.
+empty_loop = "forbid"
+# No infinite loops are needed in Rustlings.
+infinite_loop = "deny"
+# You shouldn't leak memory while still learning Rust!
+mem_forget = "deny"
+# Currently, there are no disallowed methods. This line avoids problems when developing Rustlings.
+disallowed_methods = "allow"

dev/rustlings-repo.txt

@@ -0,0 +1 @@
+This file is used to check if the user tries to run Rustlings in the repository (the method before version 6)

exercises/00_intro/intro1.rs

@@ -0,0 +1,24 @@
+// TODO: We sometimes encourage you to keep trying things on a given exercise
+// even after you already figured it out. If you got everything working and feel
+// ready for the next exercise, enter `n` in the terminal.
+//
+// The exercise file will be reloaded when you change one of the lines below!
+// Try adding a new `println!` and check the updated output in the terminal.
+
+fn main() {
+    println!(r#"       Welcome to...                      "#);
+    println!(r#"                 _   _ _                  "#);
+    println!(r#"  _ __ _   _ ___| |_| (_)_ __   __ _ ___  "#);
+    println!(r#" | '__| | | / __| __| | | '_ \ / _` / __| "#);
+    println!(r#" | |  | |_| \__ \ |_| | | | | | (_| \__ \ "#);
+    println!(r#" |_|   \__,_|___/\__|_|_|_| |_|\__, |___/ "#);
+    println!(r#"                               |___/      "#);
+    println!();
+    println!("This exercise compiles successfully. The remaining exercises contain a compiler");
+    println!("or logic error. The central concept behind Rustlings is to fix these errors and");
+    println!("solve the exercises. Good luck!");
+    println!();
+    println!("The file of this exercise is `exercises/00_intro/intro1.rs`. Have a look!");
+    println!("The current exercise path will be always shown under the progress bar.");
+    println!("You can click on the path to open the exercise file in your editor.");
+}

exercises/00_intro/intro2.rs

@@ -0,0 +1,4 @@
+fn main() {
+    // TODO: Fix the code to print "Hello world!".
+    printline!("Hello world!");
+}

exercises/01_variables/README.md

@@ -1,8 +1,8 @@
 # Variables
 
 In Rust, variables are immutable by default.
-When a variable is immutable, once a value is bound to a name, you can’t change that value.
-You can make them mutable by adding mut in front of the variable name.
+When a variable is immutable, once a value is bound to a name, you can't change that value.
+You can make them mutable by adding `mut` in front of the variable name.
 
 ## Further information
 

exercises/01_variables/variables1.rs

@@ -0,0 +1,6 @@
+fn main() {
+    // TODO: Add the missing keyword.
+    x = 5;
+
+    println!("x has the value {x}");
+}

exercises/01_variables/variables2.rs

@@ -0,0 +1,10 @@
+fn main() {
+    // TODO: Change the line below to fix the compiler error.
+    let x;
+
+    if x == 10 {
+        println!("x is ten!");
+    } else {
+        println!("x is not ten!");
+    }
+}

exercises/01_variables/variables3.rs

@@ -0,0 +1,6 @@
+fn main() {
+    // TODO: Change the line below to fix the compiler error.
+    let x: i32;
+
+    println!("Number {x}");
+}

exercises/01_variables/variables4.rs

@@ -0,0 +1,8 @@
+// TODO: Fix the compiler error.
+fn main() {
+    let x = 3;
+    println!("Number {x}");
+
+    x = 5; // Don't change this line
+    println!("Number {x}");
+}

exercises/01_variables/variables5.rs

@@ -0,0 +1,8 @@
+fn main() {
+    let number = "T-H-R-E-E"; // Don't change this line
+    println!("Spell a number: {number}");
+
+    // TODO: Fix the compiler error by changing the line below without renaming the variable.
+    number = 3;
+    println!("Number plus two is: {}", number + 2);
+}

exercises/01_variables/variables6.rs

@@ -0,0 +1,6 @@
+// TODO: Change the line below to fix the compiler error.
+const NUMBER = 3;
+
+fn main() {
+    println!("Number: {NUMBER}");
+}

exercises/02_functions/README.md

@@ -1,6 +1,7 @@
 # Functions
 
-Here, you'll learn how to write functions and how Rust's compiler can trace things way back.
+Here, you'll learn how to write functions and how the Rust compiler can help you debug errors even
+in more complex code.
 
 ## Further information
 

exercises/02_functions/functions1.rs

@@ -0,0 +1,5 @@
+// TODO: Add some function with the name `call_me` without arguments or a return value.
+
+fn main() {
+    call_me(); // Don't change this line
+}

exercises/02_functions/functions2.rs

@@ -1,14 +1,10 @@
-// functions2.rs
-// Make me compile! Execute `rustlings hint functions2` for hints :)
-
-// I AM NOT DONE
-
-fn main() {
-    call_me(3);
-}
-
+// TODO: Add the missing type of the argument `num` after the colon `:`.
 fn call_me(num:) {
     for i in 0..num {
         println!("Ring! Call number {}", i + 1);
     }
 }
+
+fn main() {
+    call_me(3);
+}

exercises/02_functions/functions3.rs

@@ -0,0 +1,10 @@
+fn call_me(num: u8) {
+    for i in 0..num {
+        println!("Ring! Call number {}", i + 1);
+    }
+}
+
+fn main() {
+    // TODO: Fix the function call.
+    call_me();
+}

exercises/02_functions/functions4.rs

@@ -0,0 +1,22 @@
+// This store is having a sale where if the price is an even number, you get 10
+// Rustbucks off, but if it's an odd number, it's 3 Rustbucks off.
+// Don't worry about the function bodies themselves, we are only interested in
+// the signatures for now.
+
+fn is_even(num: i64) -> bool {
+    num % 2 == 0
+}
+
+// TODO: Fix the function signature.
+fn sale_price(price: i64) -> {
+    if is_even(price) {
+        price - 10
+    } else {
+        price - 3
+    }
+}
+
+fn main() {
+    let original_price = 51;
+    println!("Your sale price is {}", sale_price(original_price));
+}

exercises/02_functions/functions5.rs

@@ -0,0 +1,9 @@
+// TODO: Fix the function body without changing the signature.
+fn square(num: i32) -> i32 {
+    num * num;
+}
+
+fn main() {
+    let answer = square(3);
+    println!("The square of 3 is {answer}");
+}

exercises/03_if/README.md

@@ -1,6 +1,6 @@
 # If
 
-`if`, the most basic type of control flow, is what you'll learn here.
+`if`, the most basic (but still surprisingly versatile!) type of control flow, is what you'll learn here.
 
 ## Further information
 

exercises/03_if/if1.rs

@@ -1,13 +1,13 @@
-// if1.rs
-
-// I AM NOT DONE
-
-pub fn bigger(a: i32, b: i32) -> i32 {
-    // Complete this function to return the bigger number!
+fn bigger(a: i32, b: i32) -> i32 {
+    // TODO: Complete this function to return the bigger number!
+    // If both numbers are equal, any of them can be returned.
     // Do not use:
     // - another function call
     // - additional variables
-    // Execute `rustlings hint if1` for hints
+}
+
+fn main() {
+    // You can optionally experiment here.
 }
 
 // Don't mind this for now :)
@@ -24,4 +24,9 @@ mod tests {
     fn fortytwo_is_bigger_than_thirtytwo() {
         assert_eq!(42, bigger(32, 42));
     }
+
+    #[test]
+    fn equal_numbers() {
+        assert_eq!(42, bigger(42, 42));
+    }
 }

exercises/03_if/if2.rs

@@ -0,0 +1,37 @@
+// TODO: Fix the compiler error on this function.
+fn picky_eater(food: &str) -> &str {
+    if food == "strawberry" {
+        "Yummy!"
+    } else {
+        1
+    }
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+// TODO: Read the tests to understand the desired behavior.
+// Make all tests pass without changing them.
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn yummy_food() {
+        // This means that calling `picky_eater` with the argument "strawberry" should return "Yummy!".
+        assert_eq!(picky_eater("strawberry"), "Yummy!");
+    }
+
+    #[test]
+    fn neutral_food() {
+        assert_eq!(picky_eater("potato"), "I guess I can eat that.");
+    }
+
+    #[test]
+    fn default_disliked_food() {
+        assert_eq!(picky_eater("broccoli"), "No thanks!");
+        assert_eq!(picky_eater("gummy bears"), "No thanks!");
+        assert_eq!(picky_eater("literally anything"), "No thanks!");
+    }
+}

exercises/03_if/if3.rs

@@ -0,0 +1,53 @@
+fn animal_habitat(animal: &str) -> &str {
+    // TODO: Fix the compiler error in the statement below.
+    let identifier = if animal == "crab" {
+        1
+    } else if animal == "gopher" {
+        2.0
+    } else if animal == "snake" {
+        3
+    } else {
+        "Unknown"
+    };
+
+    // Don't change the expression below!
+    if identifier == 1 {
+        "Beach"
+    } else if identifier == 2 {
+        "Burrow"
+    } else if identifier == 3 {
+        "Desert"
+    } else {
+        "Unknown"
+    }
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+// Don't change the tests!
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn gopher_lives_in_burrow() {
+        assert_eq!(animal_habitat("gopher"), "Burrow")
+    }
+
+    #[test]
+    fn snake_lives_in_desert() {
+        assert_eq!(animal_habitat("snake"), "Desert")
+    }
+
+    #[test]
+    fn crab_lives_on_beach() {
+        assert_eq!(animal_habitat("crab"), "Beach")
+    }
+
+    #[test]
+    fn unknown_animal() {
+        assert_eq!(animal_habitat("dinosaur"), "Unknown")
+    }
+}

exercises/04_primitive_types/README.md

@@ -5,5 +5,5 @@ compiler. In this section, we'll go through the most important ones.
 
 ## Further information
 
-- [Data Types](https://doc.rust-lang.org/stable/book/ch03-02-data-types.html)
-- [The Slice Type](https://doc.rust-lang.org/stable/book/ch04-03-slices.html)
+- [Data Types](https://doc.rust-lang.org/book/ch03-02-data-types.html)
+- [The Slice Type](https://doc.rust-lang.org/book/ch04-03-slices.html)

exercises/04_primitive_types/primitive_types1.rs

@@ -0,0 +1,15 @@
+// Booleans (`bool`)
+
+fn main() {
+    let is_morning = true;
+    if is_morning {
+        println!("Good morning!");
+    }
+
+    // TODO: Define a boolean variable with the name `is_evening` before the `if` statement below.
+    // The value of the variable should be the negation (opposite) of `is_morning`.
+    // let …
+    if is_evening {
+        println!("Good evening!");
+    }
+}

exercises/04_primitive_types/primitive_types2.rs

@@ -0,0 +1,28 @@
+// Characters (`char`)
+
+fn main() {
+    // Note the _single_ quotes, these are different from the double quotes
+    // you've been seeing around.
+    let my_first_initial = 'C';
+    if my_first_initial.is_alphabetic() {
+        println!("Alphabetical!");
+    } else if my_first_initial.is_numeric() {
+        println!("Numerical!");
+    } else {
+        println!("Neither alphabetic nor numeric!");
+    }
+
+    // TODO: Analogous to the example before, declare a variable called `your_character`
+    // below with your favorite character.
+    // Try a letter, try a digit (in single quotes), try a special character, try a character
+    // from a different language than your own, try an emoji 😉
+    // let your_character = '';
+
+    if your_character.is_alphabetic() {
+        println!("Alphabetical!");
+    } else if your_character.is_numeric() {
+        println!("Numerical!");
+    } else {
+        println!("Neither alphabetic nor numeric!");
+    }
+}

exercises/04_primitive_types/primitive_types3.rs

@@ -0,0 +1,11 @@
+fn main() {
+    // TODO: Create an array called `a` with at least 100 elements in it.
+    // let a = ???
+
+    if a.len() >= 100 {
+        println!("Wow, that's a big array!");
+    } else {
+        println!("Meh, I eat arrays like that for breakfast.");
+        panic!("Array not big enough, more elements needed");
+    }
+}

exercises/04_primitive_types/primitive_types4.rs

@@ -0,0 +1,16 @@
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn slice_out_of_array() {
+        let a = [1, 2, 3, 4, 5];
+
+        // TODO: Get a slice called `nice_slice` out of the array `a` so that the test passes.
+        // let nice_slice = ???
+
+        assert_eq!([2, 3, 4], nice_slice);
+    }
+}

exercises/04_primitive_types/primitive_types5.rs

@@ -0,0 +1,8 @@
+fn main() {
+    let cat = ("Furry McFurson", 3.5);
+
+    // TODO: Destructure the `cat` tuple in one statement so that the println works.
+    // let /* your pattern here */ = cat;
+
+    println!("{name} is {age} years old");
+}

exercises/04_primitive_types/primitive_types6.rs

@@ -0,0 +1,17 @@
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn indexing_tuple() {
+        let numbers = (1, 2, 3);
+
+        // TODO: Use a tuple index to access the second element of `numbers`
+        // and assign it to a variable called `second`.
+        // let second = ???;
+
+        assert_eq!(second, 2, "This is not the 2nd number in the tuple!");
+    }
+}

exercises/05_vecs/README.md

@@ -0,0 +1,17 @@
+# Vectors
+
+Vectors are one of the most-used Rust data structures. In other programming
+languages, they'd simply be called Arrays, but since Rust operates on a
+bit of a lower level, an array in Rust is stored on the stack (meaning it
+can't grow or shrink, and the size needs to be known at compile time),
+and a Vector is stored in the heap (where these restrictions do not apply).
+
+Vectors are a bit of a later chapter in the book, but we think that they're
+useful enough to talk about them a bit earlier. We shall be talking about
+the other useful data structure, hash maps, later.
+
+## Further information
+
+- [Storing Lists of Values with Vectors](https://doc.rust-lang.org/book/ch08-01-vectors.html)
+- [`iter_mut`](https://doc.rust-lang.org/std/primitive.slice.html#method.iter_mut)
+- [`map`](https://doc.rust-lang.org/std/iter/trait.Iterator.html#method.map)

exercises/05_vecs/vecs1.rs

@@ -0,0 +1,24 @@
+fn array_and_vec() -> ([i32; 4], Vec<i32>) {
+    let a = [10, 20, 30, 40]; // Array
+
+    // TODO: Create a vector called `v` which contains the exact same elements as in the array `a`.
+    // Use the vector macro.
+    // let v = ???;
+
+    (a, v)
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_array_and_vec_similarity() {
+        let (a, v) = array_and_vec();
+        assert_eq!(a, *v);
+    }
+}

exercises/05_vecs/vecs2.rs

@@ -0,0 +1,60 @@
+fn vec_loop(input: &[i32]) -> Vec<i32> {
+    let mut output = Vec::new();
+
+    for element in input {
+        // TODO: Multiply each element in the `input` slice by 2 and push it to
+        // the `output` vector.
+    }
+
+    output
+}
+
+fn vec_map_example(input: &[i32]) -> Vec<i32> {
+    // An example of collecting a vector after mapping.
+    // We map each element of the `input` slice to its value plus 1.
+    // If the input is `[1, 2, 3]`, the output is `[2, 3, 4]`.
+    input.iter().map(|element| element + 1).collect()
+}
+
+fn vec_map(input: &[i32]) -> Vec<i32> {
+    // TODO: Here, we also want to multiply each element in the `input` slice
+    // by 2, but with iterator mapping instead of manually pushing into an empty
+    // vector.
+    // See the example in the function `vec_map_example` above.
+    input
+        .iter()
+        .map(|element| {
+            // ???
+        })
+        .collect()
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_vec_loop() {
+        let input = [2, 4, 6, 8, 10];
+        let ans = vec_loop(&input);
+        assert_eq!(ans, [4, 8, 12, 16, 20]);
+    }
+
+    #[test]
+    fn test_vec_map_example() {
+        let input = [1, 2, 3];
+        let ans = vec_map_example(&input);
+        assert_eq!(ans, [2, 3, 4]);
+    }
+
+    #[test]
+    fn test_vec_map() {
+        let input = [2, 4, 6, 8, 10];
+        let ans = vec_map(&input);
+        assert_eq!(ans, [4, 8, 12, 16, 20]);
+    }
+}

exercises/06_move_semantics/move_semantics1.rs

@@ -0,0 +1,24 @@
+// TODO: Fix the compiler error in this function.
+fn fill_vec(vec: Vec<i32>) -> Vec<i32> {
+    let vec = vec;
+
+    vec.push(88);
+
+    vec
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn move_semantics1() {
+        let vec0 = vec![22, 44, 66];
+        let vec1 = fill_vec(vec0);
+        assert_eq!(vec1, vec![22, 44, 66, 88]);
+    }
+}

exercises/06_move_semantics/move_semantics2.rs

@@ -0,0 +1,28 @@
+fn fill_vec(vec: Vec<i32>) -> Vec<i32> {
+    let mut vec = vec;
+
+    vec.push(88);
+
+    vec
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    // TODO: Make both vectors `vec0` and `vec1` accessible at the same time to
+    // fix the compiler error in the test.
+    #[test]
+    fn move_semantics2() {
+        let vec0 = vec![22, 44, 66];
+
+        let vec1 = fill_vec(vec0);
+
+        assert_eq!(vec0, [22, 44, 66]);
+        assert_eq!(vec1, [22, 44, 66, 88]);
+    }
+}

exercises/06_move_semantics/move_semantics3.rs

@@ -0,0 +1,22 @@
+// TODO: Fix the compiler error in the function without adding any new line.
+fn fill_vec(vec: Vec<i32>) -> Vec<i32> {
+    vec.push(88);
+
+    vec
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn move_semantics3() {
+        let vec0 = vec![22, 44, 66];
+        let vec1 = fill_vec(vec0);
+        assert_eq!(vec1, [22, 44, 66, 88]);
+    }
+}

exercises/06_move_semantics/move_semantics4.rs

@@ -0,0 +1,18 @@
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    // TODO: Fix the compiler errors only by reordering the lines in the test.
+    // Don't add, change or remove any line.
+    #[test]
+    fn move_semantics4() {
+        let mut x = Vec::new();
+        let y = &mut x;
+        let z = &mut x;
+        y.push(42);
+        z.push(13);
+        assert_eq!(x, [42, 13]);
+    }
+}

exercises/06_move_semantics/move_semantics5.rs

@@ -0,0 +1,24 @@
+#![allow(clippy::ptr_arg)]
+
+// TODO: Fix the compiler errors without changing anything except adding or
+// removing references (the character `&`).
+
+// Shouldn't take ownership
+fn get_char(data: String) -> char {
+    data.chars().last().unwrap()
+}
+
+// Should take ownership
+fn string_uppercase(mut data: &String) {
+    data = data.to_uppercase();
+
+    println!("{data}");
+}
+
+fn main() {
+    let data = "Rust is great!".to_string();
+
+    get_char(data);
+
+    string_uppercase(&data);
+}

exercises/07_structs/structs1.rs

@@ -0,0 +1,47 @@
+struct ColorRegularStruct {
+    // TODO: Add the fields that the test `regular_structs` expects.
+    // What types should the fields have? What are the minimum and maximum values for RGB colors?
+}
+
+struct ColorTupleStruct(/* TODO: Add the fields that the test `tuple_structs` expects */);
+
+#[derive(Debug)]
+struct UnitStruct;
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn regular_structs() {
+        // TODO: Instantiate a regular struct.
+        // let green =
+
+        assert_eq!(green.red, 0);
+        assert_eq!(green.green, 255);
+        assert_eq!(green.blue, 0);
+    }
+
+    #[test]
+    fn tuple_structs() {
+        // TODO: Instantiate a tuple struct.
+        // let green =
+
+        assert_eq!(green.0, 0);
+        assert_eq!(green.1, 255);
+        assert_eq!(green.2, 0);
+    }
+
+    #[test]
+    fn unit_structs() {
+        // TODO: Instantiate a unit struct.
+        // let unit_struct =
+        let message = format!("{unit_struct:?}s are fun!");
+
+        assert_eq!(message, "UnitStructs are fun!");
+    }
+}

exercises/07_structs/structs2.rs

@@ -1,8 +1,3 @@
-// structs2.rs
-// Address all the TODOs to make the tests pass!
-
-// I AM NOT DONE
-
 #[derive(Debug)]
 struct Order {
     name: String,
@@ -26,6 +21,10 @@ fn create_order_template() -> Order {
     }
 }
 
+fn main() {
+    // You can optionally experiment here.
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -33,8 +32,10 @@ mod tests {
     #[test]
     fn your_order() {
         let order_template = create_order_template();
+
         // TODO: Create your own order using the update syntax and template above!
         // let your_order =
+
         assert_eq!(your_order.name, "Hacker in Rust");
         assert_eq!(your_order.year, order_template.year);
         assert_eq!(your_order.made_by_phone, order_template.made_by_phone);

exercises/07_structs/structs3.rs

@@ -0,0 +1,87 @@
+// Structs contain data, but can also have logic. In this exercise, we have
+// defined the `Package` struct, and we want to test some logic attached to it.
+
+#[derive(Debug)]
+struct Package {
+    sender_country: String,
+    recipient_country: String,
+    weight_in_grams: u32,
+}
+
+impl Package {
+    fn new(sender_country: String, recipient_country: String, weight_in_grams: u32) -> Self {
+        if weight_in_grams < 10 {
+            // This isn't how you should handle errors in Rust, but we will
+            // learn about error handling later.
+            panic!("Can't ship a package with weight below 10 grams");
+        }
+
+        Self {
+            sender_country,
+            recipient_country,
+            weight_in_grams,
+        }
+    }
+
+    // TODO: Add the correct return type to the function signature.
+    fn is_international(&self) {
+        // TODO: Read the tests that use this method to find out when a package
+        // is considered international.
+    }
+
+    // TODO: Add the correct return type to the function signature.
+    fn get_fees(&self, cents_per_gram: u32) {
+        // TODO: Calculate the package's fees.
+    }
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    #[should_panic]
+    fn fail_creating_weightless_package() {
+        let sender_country = String::from("Spain");
+        let recipient_country = String::from("Austria");
+
+        Package::new(sender_country, recipient_country, 5);
+    }
+
+    #[test]
+    fn create_international_package() {
+        let sender_country = String::from("Spain");
+        let recipient_country = String::from("Russia");
+
+        let package = Package::new(sender_country, recipient_country, 1200);
+
+        assert!(package.is_international());
+    }
+
+    #[test]
+    fn create_local_package() {
+        let sender_country = String::from("Canada");
+        let recipient_country = sender_country.clone();
+
+        let package = Package::new(sender_country, recipient_country, 1200);
+
+        assert!(!package.is_international());
+    }
+
+    #[test]
+    fn calculate_transport_fees() {
+        let sender_country = String::from("Spain");
+        let recipient_country = String::from("Spain");
+
+        let cents_per_gram = 3;
+
+        let package = Package::new(sender_country, recipient_country, 1500);
+
+        assert_eq!(package.get_fees(cents_per_gram), 4500);
+        assert_eq!(package.get_fees(cents_per_gram * 2), 9000);
+    }
+}

exercises/08_enums/README.md

@@ -1,10 +1,10 @@
 # Enums
 
 Rust allows you to define types called "enums" which enumerate possible values.
-Enums are a feature in many languages, but their capabilities differ in each language. Rust’s enums are most similar to algebraic data types in functional languages, such as F#, OCaml, and Haskell.
+Enums are a feature in many languages, but their capabilities differ in each language. Rust's enums are most similar to algebraic data types in functional languages, such as F#, OCaml, and Haskell.
 Useful in combination with enums is Rust's "pattern matching" facility, which makes it easy to run different code for different values of an enumeration.
 
 ## Further information
 
 - [Enums](https://doc.rust-lang.org/book/ch06-00-enums.html)
-- [Pattern syntax](https://doc.rust-lang.org/book/ch18-03-pattern-syntax.html)
+- [Pattern syntax](https://doc.rust-lang.org/book/ch19-03-pattern-syntax.html)

exercises/08_enums/enums1.rs

@@ -1,16 +1,12 @@
-// enums1.rs
-// Make me compile! Execute `rustlings hint enums1` for hints!
-
-// I AM NOT DONE
-
 #[derive(Debug)]
 enum Message {
-    // TODO: define a few types of messages as used below
+    // TODO: Define a few types of messages as used below.
 }
 
 fn main() {
-    println!("{:?}", Message::Quit);
-    println!("{:?}", Message::Echo);
+    println!("{:?}", Message::Resize);
     println!("{:?}", Message::Move);
+    println!("{:?}", Message::Echo);
     println!("{:?}", Message::ChangeColor);
+    println!("{:?}", Message::Quit);
 }

exercises/08_enums/enums2.rs

@@ -1,22 +1,27 @@
-// enums2.rs
-// Make me compile! Execute `rustlings hint enums2` for hints!
-
-// I AM NOT DONE
+#[derive(Debug)]
+struct Point {
+    x: u64,
+    y: u64,
+}
 
 #[derive(Debug)]
 enum Message {
-    // TODO: define the different variants used below
+    // TODO: Define the different variants used below.
 }
 
 impl Message {
     fn call(&self) {
-        println!("{:?}", &self);
+        println!("{self:?}");
     }
 }
 
 fn main() {
     let messages = [
-        Message::Move { x: 10, y: 30 },
+        Message::Resize {
+            width: 10,
+            height: 30,
+        },
+        Message::Move(Point { x: 10, y: 15 }),
         Message::Echo(String::from("hello world")),
         Message::ChangeColor(200, 255, 255),
         Message::Quit,

exercises/08_enums/enums3.rs

@@ -0,0 +1,88 @@
+struct Point {
+    x: u64,
+    y: u64,
+}
+
+enum Message {
+    Resize { width: u64, height: u64 },
+    Move(Point),
+    Echo(String),
+    ChangeColor(u8, u8, u8),
+    Quit,
+}
+
+struct State {
+    width: u64,
+    height: u64,
+    position: Point,
+    message: String,
+    // RGB color composed of red, green and blue.
+    color: (u8, u8, u8),
+    quit: bool,
+}
+
+impl State {
+    fn resize(&mut self, width: u64, height: u64) {
+        self.width = width;
+        self.height = height;
+    }
+
+    fn move_position(&mut self, point: Point) {
+        self.position = point;
+    }
+
+    fn echo(&mut self, s: String) {
+        self.message = s;
+    }
+
+    fn change_color(&mut self, red: u8, green: u8, blue: u8) {
+        self.color = (red, green, blue);
+    }
+
+    fn quit(&mut self) {
+        self.quit = true;
+    }
+
+    fn process(&mut self, message: Message) {
+        // TODO: Create a match expression to process the different message
+        // variants using the methods defined above.
+    }
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_match_message_call() {
+        let mut state = State {
+            width: 0,
+            height: 0,
+            position: Point { x: 0, y: 0 },
+            message: String::from("hello world"),
+            color: (0, 0, 0),
+            quit: false,
+        };
+
+        state.process(Message::Resize {
+            width: 10,
+            height: 30,
+        });
+        state.process(Message::Move(Point { x: 10, y: 15 }));
+        state.process(Message::Echo(String::from("Hello world!")));
+        state.process(Message::ChangeColor(255, 0, 255));
+        state.process(Message::Quit);
+
+        assert_eq!(state.width, 10);
+        assert_eq!(state.height, 30);
+        assert_eq!(state.position.x, 10);
+        assert_eq!(state.position.y, 15);
+        assert_eq!(state.message, "Hello world!");
+        assert_eq!(state.color, (255, 0, 255));
+        assert!(state.quit);
+    }
+}

exercises/09_strings/strings1.rs

@@ -0,0 +1,9 @@
+// TODO: Fix the compiler error without changing the function signature.
+fn current_favorite_color() -> String {
+    "blue"
+}
+
+fn main() {
+    let answer = current_favorite_color();
+    println!("My current favorite color is {answer}");
+}

exercises/09_strings/strings2.rs

@@ -1,18 +1,14 @@
-// strings2.rs
-// Make me compile without changing the function signature!
-// Execute `rustlings hint strings2` for hints :)
-
-// I AM NOT DONE
+// TODO: Fix the compiler error in the `main` function without changing this function.
+fn is_a_color_word(attempt: &str) -> bool {
+    attempt == "green" || attempt == "blue" || attempt == "red"
+}
 
 fn main() {
-    let word = String::from("green"); // Try not changing this line :)
+    let word = String::from("green"); // Don't change this line.
+
     if is_a_color_word(word) {
         println!("That is a color word I know!");
     } else {
         println!("That is not a color word I know.");
     }
 }
-
-fn is_a_color_word(attempt: &str) -> bool {
-    attempt == "green" || attempt == "blue" || attempt == "red"
-}

exercises/09_strings/strings3.rs

@@ -0,0 +1,46 @@
+fn trim_me(input: &str) -> &str {
+    // TODO: Remove whitespace from both ends of a string.
+}
+
+fn compose_me(input: &str) -> String {
+    // TODO: Add " world!" to the string! There are multiple ways to do this.
+}
+
+fn replace_me(input: &str) -> String {
+    // TODO: Replace "cars" in the string with "balloons".
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn trim_a_string() {
+        assert_eq!(trim_me("Hello!     "), "Hello!");
+        assert_eq!(trim_me("  What's up!"), "What's up!");
+        assert_eq!(trim_me("   Hola!  "), "Hola!");
+        assert_eq!(trim_me("Hi!"), "Hi!");
+    }
+
+    #[test]
+    fn compose_a_string() {
+        assert_eq!(compose_me("Hello"), "Hello world!");
+        assert_eq!(compose_me("Goodbye"), "Goodbye world!");
+    }
+
+    #[test]
+    fn replace_a_string() {
+        assert_eq!(
+            replace_me("I think cars are cool"),
+            "I think balloons are cool",
+        );
+        assert_eq!(
+            replace_me("I love to look at cars"),
+            "I love to look at balloons",
+        );
+    }
+}

exercises/09_strings/strings4.rs

@@ -0,0 +1,37 @@
+// Calls of this function should be replaced with calls of `string_slice` or `string`.
+fn placeholder() {}
+
+fn string_slice(arg: &str) {
+    println!("{arg}");
+}
+
+fn string(arg: String) {
+    println!("{arg}");
+}
+
+// TODO: Here are a bunch of values - some are `String`, some are `&str`.
+// Your task is to replace `placeholder(…)` with either `string_slice(…)`
+// or `string(…)` depending on what you think each value is.
+fn main() {
+    placeholder("blue");
+
+    placeholder("red".to_string());
+
+    placeholder(String::from("hi"));
+
+    placeholder("rust is fun!".to_owned());
+
+    placeholder("nice weather".into());
+
+    placeholder(format!("Interpolation {}", "Station"));
+
+    // WARNING: This is byte indexing, not character indexing.
+    // Character indexing can be done using `s.chars().nth(INDEX)`.
+    placeholder(&String::from("abc")[0..1]);
+
+    placeholder("  hello there ".trim());
+
+    placeholder("Happy Monday!".replace("Mon", "Tues"));
+
+    placeholder("mY sHiFt KeY iS sTiCkY".to_lowercase());
+}

exercises/10_modules/modules1.rs

@@ -1,8 +1,4 @@
-// modules1.rs
-// Make me compile! Execute `rustlings hint modules1` for hints :)
-
-// I AM NOT DONE
-
+// TODO: Fix the compiler error about calling a private function.
 mod sausage_factory {
     // Don't let anybody outside of this module see this!
     fn get_secret_recipe() -> String {

exercises/10_modules/modules2.rs

@@ -0,0 +1,26 @@
+// You can bring module paths into scopes and provide new names for them with
+// the `use` and `as` keywords.
+
+mod delicious_snacks {
+    // TODO: Add the following two `use` statements after fixing them.
+    // use self::fruits::PEAR as ???;
+    // use self::veggies::CUCUMBER as ???;
+
+    mod fruits {
+        pub const PEAR: &str = "Pear";
+        pub const APPLE: &str = "Apple";
+    }
+
+    mod veggies {
+        pub const CUCUMBER: &str = "Cucumber";
+        pub const CARROT: &str = "Carrot";
+    }
+}
+
+fn main() {
+    println!(
+        "favorite snacks: {} and {}",
+        delicious_snacks::fruit,
+        delicious_snacks::veggie,
+    );
+}

exercises/10_modules/modules3.rs

@@ -0,0 +1,13 @@
+// You can use the `use` keyword to bring module paths from modules from
+// anywhere and especially from the standard library into your scope.
+
+// TODO: Bring `SystemTime` and `UNIX_EPOCH` from the `std::time` module into
+// your scope. Bonus style points if you can do it with one line!
+// use ???;
+
+fn main() {
+    match SystemTime::now().duration_since(UNIX_EPOCH) {
+        Ok(n) => println!("1970-01-01 00:00:00 UTC was {} seconds ago!", n.as_secs()),
+        Err(_) => panic!("SystemTime before UNIX EPOCH!"),
+    }
+}

exercises/11_hashmaps/README.md

@@ -0,0 +1,12 @@
+# Hashmaps
+
+A *hash map* allows you to associate a value with a particular key.
+You may also know this by the names [*unordered map* in C++](https://en.cppreference.com/w/cpp/container/unordered_map),
+[*dictionary* in Python](https://docs.python.org/3/tutorial/datastructures.html#dictionaries) or an *associative array* in other languages.
+
+This is the other data structure that we've been talking about before, when
+talking about Vecs.
+
+## Further information
+
+- [Storing Keys with Associated Values in Hash Maps](https://doc.rust-lang.org/book/ch08-03-hash-maps.html)

exercises/11_hashmaps/hashmaps1.rs

@@ -1,31 +1,27 @@
-// hashmap1.rs
-// A basket of fruits in the form of a hash map needs to be defined.
-// The key represents the name of the fruit and the value represents
-// how many of that particular fruit is in the basket. You have to put
-// at least three different types of fruits (e.g apple, banana, mango)
-// in the basket and the total count of all the fruits should be at
-// least five.
-//
-// Make me compile and pass the tests!
-//
-// Execute the command `rustlings hint hashmap1` if you need
-// hints.
-
-// I AM NOT DONE
+// A basket of fruits in the form of a hash map needs to be defined. The key
+// represents the name of the fruit and the value represents how many of that
+// particular fruit is in the basket. You have to put at least 3 different
+// types of fruits (e.g. apple, banana, mango) in the basket and the total count
+// of all the fruits should be at least 5.
 
 use std::collections::HashMap;
 
 fn fruit_basket() -> HashMap<String, u32> {
-    let mut basket = // TODO: declare your hash map here.
+    // TODO: Declare the hash map.
+    // let mut basket =
 
     // Two bananas are already given for you :)
     basket.insert(String::from("banana"), 2);
 
-    // TODO: Put more fruits in your basket here.
+    // TODO: Put more fruits in your basket.
 
     basket
 }
 
+fn main() {
+    // You can optionally experiment here.
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;

exercises/11_hashmaps/hashmaps2.rs

@@ -0,0 +1,97 @@
+// We're collecting different fruits to bake a delicious fruit cake. For this,
+// we have a basket, which we'll represent in the form of a hash map. The key
+// represents the name of each fruit we collect and the value represents how
+// many of that particular fruit we have collected. Three types of fruits -
+// Apple (4), Mango (2) and Lychee (5) are already in the basket hash map. You
+// must add fruit to the basket so that there is at least one of each kind and
+// more than 11 in total - we have a lot of mouths to feed. You are not allowed
+// to insert any more of the fruits that are already in the basket (Apple,
+// Mango, and Lychee).
+
+use std::collections::HashMap;
+
+#[derive(Hash, PartialEq, Eq, Debug)]
+enum Fruit {
+    Apple,
+    Banana,
+    Mango,
+    Lychee,
+    Pineapple,
+}
+
+fn fruit_basket(basket: &mut HashMap<Fruit, u32>) {
+    let fruit_kinds = [
+        Fruit::Apple,
+        Fruit::Banana,
+        Fruit::Mango,
+        Fruit::Lychee,
+        Fruit::Pineapple,
+    ];
+
+    for fruit in fruit_kinds {
+        // TODO: Insert new fruits if they are not already present in the
+        // basket. Note that you are not allowed to put any type of fruit that's
+        // already present!
+    }
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    // Don't modify this function!
+    fn get_fruit_basket() -> HashMap<Fruit, u32> {
+        let content = [(Fruit::Apple, 4), (Fruit::Mango, 2), (Fruit::Lychee, 5)];
+        HashMap::from_iter(content)
+    }
+
+    #[test]
+    fn test_given_fruits_are_not_modified() {
+        let mut basket = get_fruit_basket();
+        fruit_basket(&mut basket);
+        assert_eq!(*basket.get(&Fruit::Apple).unwrap(), 4);
+        assert_eq!(*basket.get(&Fruit::Mango).unwrap(), 2);
+        assert_eq!(*basket.get(&Fruit::Lychee).unwrap(), 5);
+    }
+
+    #[test]
+    fn at_least_five_types_of_fruits() {
+        let mut basket = get_fruit_basket();
+        fruit_basket(&mut basket);
+        let count_fruit_kinds = basket.len();
+        assert!(count_fruit_kinds >= 5);
+    }
+
+    #[test]
+    fn greater_than_eleven_fruits() {
+        let mut basket = get_fruit_basket();
+        fruit_basket(&mut basket);
+        let count = basket.values().sum::<u32>();
+        assert!(count > 11);
+    }
+
+    #[test]
+    fn all_fruit_types_in_basket() {
+        let fruit_kinds = [
+            Fruit::Apple,
+            Fruit::Banana,
+            Fruit::Mango,
+            Fruit::Lychee,
+            Fruit::Pineapple,
+        ];
+
+        let mut basket = get_fruit_basket();
+        fruit_basket(&mut basket);
+
+        for fruit_kind in fruit_kinds {
+            let Some(amount) = basket.get(&fruit_kind) else {
+                panic!("Fruit kind {fruit_kind:?} was not found in basket");
+            };
+            assert!(*amount > 0);
+        }
+    }
+}

exercises/11_hashmaps/hashmaps3.rs

@@ -0,0 +1,77 @@
+// A list of scores (one per line) of a soccer match is given. Each line is of
+// the form "<team_1_name>,<team_2_name>,<team_1_goals>,<team_2_goals>"
+// Example: "England,France,4,2" (England scored 4 goals, France 2).
+//
+// You have to build a scores table containing the name of the team, the total
+// number of goals the team scored, and the total number of goals the team
+// conceded.
+
+use std::collections::HashMap;
+
+// A structure to store the goal details of a team.
+#[derive(Default)]
+struct TeamScores {
+    goals_scored: u8,
+    goals_conceded: u8,
+}
+
+fn build_scores_table(results: &str) -> HashMap<&str, TeamScores> {
+    // The name of the team is the key and its associated struct is the value.
+    let mut scores = HashMap::<&str, TeamScores>::new();
+
+    for line in results.lines() {
+        let mut split_iterator = line.split(',');
+        // NOTE: We use `unwrap` because we didn't deal with error handling yet.
+        let team_1_name = split_iterator.next().unwrap();
+        let team_2_name = split_iterator.next().unwrap();
+        let team_1_score: u8 = split_iterator.next().unwrap().parse().unwrap();
+        let team_2_score: u8 = split_iterator.next().unwrap().parse().unwrap();
+
+        // TODO: Populate the scores table with the extracted details.
+        // Keep in mind that goals scored by team 1 will be the number of goals
+        // conceded by team 2. Similarly, goals scored by team 2 will be the
+        // number of goals conceded by team 1.
+    }
+
+    scores
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    const RESULTS: &str = "England,France,4,2
+France,Italy,3,1
+Poland,Spain,2,0
+Germany,England,2,1
+England,Spain,1,0";
+
+    #[test]
+    fn build_scores() {
+        let scores = build_scores_table(RESULTS);
+
+        assert!(["England", "France", "Germany", "Italy", "Poland", "Spain"]
+            .into_iter()
+            .all(|team_name| scores.contains_key(team_name)));
+    }
+
+    #[test]
+    fn validate_team_score_1() {
+        let scores = build_scores_table(RESULTS);
+        let team = scores.get("England").unwrap();
+        assert_eq!(team.goals_scored, 6);
+        assert_eq!(team.goals_conceded, 4);
+    }
+
+    #[test]
+    fn validate_team_score_2() {
+        let scores = build_scores_table(RESULTS);
+        let team = scores.get("Spain").unwrap();
+        assert_eq!(team.goals_scored, 0);
+        assert_eq!(team.goals_conceded, 3);
+    }
+}

exercises/12_options/README.md

@@ -1,7 +1,8 @@
-# Option
+# Options
 
 Type Option represents an optional value: every Option is either Some and contains a value, or None, and does not.
 Option types are very common in Rust code, as they have a number of uses:
+
 - Initial values
 - Return values for functions that are not defined over their entire input range (partial functions)
 - Return value for otherwise reporting simple errors, where None is returned on error
@@ -13,7 +14,7 @@ Option types are very common in Rust code, as they have a number of uses:
 
 ## Further Information
 
-- [Option Enum Format](https://doc.rust-lang.org/stable/book/ch10-01-syntax.html#in-enum-definitions)
+- [Option Enum Format](https://doc.rust-lang.org/book/ch10-01-syntax.html#in-enum-definitions)
 - [Option Module Documentation](https://doc.rust-lang.org/std/option/)
 - [Option Enum Documentation](https://doc.rust-lang.org/std/option/enum.Option.html)
 - [if let](https://doc.rust-lang.org/rust-by-example/flow_control/if_let.html)

exercises/12_options/options1.rs

@@ -0,0 +1,36 @@
+// This function returns how much ice cream there is left in the fridge.
+// If it's before 22:00 (24-hour system), then 5 scoops are left. At 22:00,
+// someone eats it all, so no ice cream is left (value 0). Return `None` if
+// `hour_of_day` is higher than 23.
+fn maybe_ice_cream(hour_of_day: u16) -> Option<u16> {
+    // TODO: Complete the function body.
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn raw_value() {
+        // TODO: Fix this test. How do you get the value contained in the
+        // Option?
+        let ice_creams = maybe_ice_cream(12);
+
+        assert_eq!(ice_creams, 5); // Don't change this line.
+    }
+
+    #[test]
+    fn check_ice_cream() {
+        assert_eq!(maybe_ice_cream(0), Some(5));
+        assert_eq!(maybe_ice_cream(9), Some(5));
+        assert_eq!(maybe_ice_cream(18), Some(5));
+        assert_eq!(maybe_ice_cream(22), Some(0));
+        assert_eq!(maybe_ice_cream(23), Some(0));
+        assert_eq!(maybe_ice_cream(24), None);
+        assert_eq!(maybe_ice_cream(25), None);
+    }
+}

exercises/12_options/options2.rs

@@ -0,0 +1,39 @@
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn simple_option() {
+        let target = "rustlings";
+        let optional_target = Some(target);
+
+        // TODO: Make this an if-let statement whose value is `Some`.
+        word = optional_target {
+            assert_eq!(word, target);
+        }
+    }
+
+    #[test]
+    fn layered_option() {
+        let range = 10;
+        let mut optional_integers: Vec<Option<i8>> = vec![None];
+
+        for i in 1..=range {
+            optional_integers.push(Some(i));
+        }
+
+        let mut cursor = range;
+
+        // TODO: Make this a while-let statement. Remember that `Vec::pop()`
+        // adds another layer of `Option`. You can do nested pattern matching
+        // in if-let and while-let statements.
+        integer = optional_integers.pop() {
+            assert_eq!(integer, cursor);
+            cursor -= 1;
+        }
+
+        assert_eq!(cursor, 0);
+    }
+}

exercises/12_options/options3.rs

@@ -0,0 +1,17 @@
+#[derive(Debug)]
+struct Point {
+    x: i32,
+    y: i32,
+}
+
+fn main() {
+    let optional_point = Some(Point { x: 100, y: 200 });
+
+    // TODO: Fix the compiler error by adding something to this match statement.
+    match optional_point {
+        Some(p) => println!("Coordinates are {},{}", p.x, p.y),
+        _ => panic!("No match!"),
+    }
+
+    println!("{optional_point:?}"); // Don't change this line.
+}

exercises/13_error_handling/README.md

@@ -1,7 +1,8 @@
 # Error handling
-Most errors aren’t serious enough to require the program to stop entirely. 
-Sometimes, when a function fails, it’s for a reason that you can easily interpret and respond to.
-For example, if you try to open a file and that operation fails because the file doesn’t exist, you might want to create the file instead of terminating the process.
+
+Most errors aren't serious enough to require the program to stop entirely.
+Sometimes, when a function fails, it's for a reason that you can easily interpret and respond to.
+For example, if you try to open a file and that operation fails because the file doesn't exist, you might want to create the file instead of terminating the process.
 
 ## Further information
 

exercises/13_error_handling/errors1.rs

@@ -0,0 +1,41 @@
+// TODO: This function refuses to generate text to be printed on a nametag if
+// you pass it an empty string. It'd be nicer if it explained what the problem
+// was instead of just returning `None`. Thankfully, Rust has a similar
+// construct to `Option` that can be used to express error conditions. Change
+// the function signature and body to return `Result<String, String>` instead
+// of `Option<String>`.
+fn generate_nametag_text(name: String) -> Option<String> {
+    if name.is_empty() {
+        // Empty names aren't allowed
+        None
+    } else {
+        Some(format!("Hi! My name is {name}"))
+    }
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn generates_nametag_text_for_a_nonempty_name() {
+        assert_eq!(
+            generate_nametag_text("Beyoncé".to_string()).as_deref(),
+            Ok("Hi! My name is Beyoncé"),
+        );
+    }
+
+    #[test]
+    fn explains_why_generating_nametag_text_fails() {
+        assert_eq!(
+            generate_nametag_text(String::new())
+                .as_ref()
+                .map_err(|e| e.as_str()),
+            Err("Empty names aren't allowed"),
+        );
+    }
+}

exercises/13_error_handling/errors2.rs

@@ -1,36 +1,39 @@
-// errors2.rs
 // Say we're writing a game where you can buy items with tokens. All items cost
 // 5 tokens, and whenever you purchase items there is a processing fee of 1
-// token. A player of the game will type in how many items they want to buy,
-// and the `total_cost` function will calculate the total number of tokens.
-// Since the player typed in the quantity, though, we get it as a string-- and
-// they might have typed anything, not just numbers!
-
-// Right now, this function isn't handling the error case at all (and isn't
-// handling the success case properly either). What we want to do is:
-// if we call the `parse` function on a string that is not a number, that
-// function will return a `ParseIntError`, and in that case, we want to
-// immediately return that error from our function and not try to multiply
-// and add.
-
-// There are at least two ways to implement this that are both correct-- but
-// one is a lot shorter! Execute `rustlings hint errors2` for hints to both ways.
-
-// I AM NOT DONE
+// token. A player of the game will type in how many items they want to buy, and
+// the `total_cost` function will calculate the total cost of the items. Since
+// the player typed in the quantity, we get it as a string. They might have
+// typed anything, not just numbers!
+//
+// Right now, this function isn't handling the error case at all. What we want
+// to do is: If we call the `total_cost` function on a string that is not a
+// number, that function will return a `ParseIntError`. In that case, we want to
+// immediately return that error from our function and not try to multiply and
+// add.
+//
+// There are at least two ways to implement this that are both correct. But one
+// is a lot shorter!
 
 use std::num::ParseIntError;
 
-pub fn total_cost(item_quantity: &str) -> Result<i32, ParseIntError> {
+fn total_cost(item_quantity: &str) -> Result<i32, ParseIntError> {
     let processing_fee = 1;
     let cost_per_item = 5;
+
+    // TODO: Handle the error case as described above.
     let qty = item_quantity.parse::<i32>();
 
     Ok(qty * cost_per_item + processing_fee)
 }
 
+fn main() {
+    // You can optionally experiment here.
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
+    use std::num::IntErrorKind;
 
     #[test]
     fn item_quantity_is_a_valid_number() {
@@ -40,8 +43,8 @@ mod tests {
     #[test]
     fn item_quantity_is_an_invalid_number() {
         assert_eq!(
-            total_cost("beep boop").unwrap_err().to_string(),
-            "invalid digit found in string"
+            total_cost("beep boop").unwrap_err().kind(),
+            &IntErrorKind::InvalidDigit,
         );
     }
 }

exercises/13_error_handling/errors3.rs

@@ -1,31 +1,31 @@
-// errors3.rs
 // This is a program that is trying to use a completed version of the
 // `total_cost` function from the previous exercise. It's not working though!
 // Why not? What should we do to fix it?
-// Execute `rustlings hint errors3` for hints!
-
-// I AM NOT DONE
 
 use std::num::ParseIntError;
 
-fn main() {
-    let mut tokens = 100;
-    let pretend_user_input = "8";
-
-    let cost = total_cost(pretend_user_input)?;
-
-    if cost > tokens {
-        println!("You can't afford that many!");
-    } else {
-        tokens -= cost;
-        println!("You now have {} tokens.", tokens);
-    }
-}
-
-pub fn total_cost(item_quantity: &str) -> Result<i32, ParseIntError> {
+// Don't change this function.
+fn total_cost(item_quantity: &str) -> Result<i32, ParseIntError> {
     let processing_fee = 1;
     let cost_per_item = 5;
     let qty = item_quantity.parse::<i32>()?;
 
     Ok(qty * cost_per_item + processing_fee)
 }
+
+// TODO: Fix the compiler error by changing the signature and body of the
+// `main` function.
+fn main() {
+    let mut tokens = 100;
+    let pretend_user_input = "8";
+
+    // Don't change this line.
+    let cost = total_cost(pretend_user_input)?;
+
+    if cost > tokens {
+        println!("You can't afford that many!");
+    } else {
+        tokens -= cost;
+        println!("You now have {tokens} tokens.");
+    }
+}

exercises/13_error_handling/errors4.rs

@@ -0,0 +1,37 @@
+#[derive(PartialEq, Debug)]
+enum CreationError {
+    Negative,
+    Zero,
+}
+
+#[derive(PartialEq, Debug)]
+struct PositiveNonzeroInteger(u64);
+
+impl PositiveNonzeroInteger {
+    fn new(value: i64) -> Result<Self, CreationError> {
+        // TODO: This function shouldn't always return an `Ok`.
+        Ok(Self(value as u64))
+    }
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_creation() {
+        assert_eq!(
+            PositiveNonzeroInteger::new(10),
+            Ok(PositiveNonzeroInteger(10)),
+        );
+        assert_eq!(
+            PositiveNonzeroInteger::new(-10),
+            Err(CreationError::Negative),
+        );
+        assert_eq!(PositiveNonzeroInteger::new(0), Err(CreationError::Zero));
+    }
+}

exercises/13_error_handling/errors5.rs

@@ -0,0 +1,56 @@
+// This exercise is an altered version of the `errors4` exercise. It uses some
+// concepts that we won't get to until later in the course, like `Box` and the
+// `From` trait. It's not important to understand them in detail right now, but
+// you can read ahead if you like. For now, think of the `Box<dyn ???>` type as
+// an "I want anything that does ???" type.
+//
+// In short, this particular use case for boxes is for when you want to own a
+// value and you care only that it is a type which implements a particular
+// trait. To do so, the `Box` is declared as of type `Box<dyn Trait>` where
+// `Trait` is the trait the compiler looks for on any value used in that
+// context. For this exercise, that context is the potential errors which
+// can be returned in a `Result`.
+
+use std::error::Error;
+use std::fmt;
+
+#[derive(PartialEq, Debug)]
+enum CreationError {
+    Negative,
+    Zero,
+}
+
+// This is required so that `CreationError` can implement `Error`.
+impl fmt::Display for CreationError {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        let description = match *self {
+            CreationError::Negative => "number is negative",
+            CreationError::Zero => "number is zero",
+        };
+        f.write_str(description)
+    }
+}
+
+impl Error for CreationError {}
+
+#[derive(PartialEq, Debug)]
+struct PositiveNonzeroInteger(u64);
+
+impl PositiveNonzeroInteger {
+    fn new(value: i64) -> Result<PositiveNonzeroInteger, CreationError> {
+        match value {
+            x if x < 0 => Err(CreationError::Negative),
+            0 => Err(CreationError::Zero),
+            x => Ok(PositiveNonzeroInteger(x as u64)),
+        }
+    }
+}
+
+// TODO: Add the correct return type `Result<(), Box<dyn ???>>`. What can we
+// use to describe both errors? Is there a trait which both errors implement?
+fn main() {
+    let pretend_user_input = "42";
+    let x: i64 = pretend_user_input.parse()?;
+    println!("output={:?}", PositiveNonzeroInteger::new(x)?);
+    Ok(())
+}

exercises/13_error_handling/errors6.rs

@@ -0,0 +1,89 @@
+// Using catch-all error types like `Box<dyn Error>` isn't recommended for
+// library code where callers might want to make decisions based on the error
+// content instead of printing it out or propagating it further. Here, we define
+// a custom error type to make it possible for callers to decide what to do next
+// when our function returns an error.
+
+use std::num::ParseIntError;
+
+#[derive(PartialEq, Debug)]
+enum CreationError {
+    Negative,
+    Zero,
+}
+
+// A custom error type that we will be using in `PositiveNonzeroInteger::parse`.
+#[derive(PartialEq, Debug)]
+enum ParsePosNonzeroError {
+    Creation(CreationError),
+    ParseInt(ParseIntError),
+}
+
+impl ParsePosNonzeroError {
+    fn from_creation(err: CreationError) -> Self {
+        Self::Creation(err)
+    }
+
+    // TODO: Add another error conversion function here.
+    // fn from_parse_int(???) -> Self { ??? }
+}
+
+#[derive(PartialEq, Debug)]
+struct PositiveNonzeroInteger(u64);
+
+impl PositiveNonzeroInteger {
+    fn new(value: i64) -> Result<Self, CreationError> {
+        match value {
+            x if x < 0 => Err(CreationError::Negative),
+            0 => Err(CreationError::Zero),
+            x => Ok(Self(x as u64)),
+        }
+    }
+
+    fn parse(s: &str) -> Result<Self, ParsePosNonzeroError> {
+        // TODO: change this to return an appropriate error instead of panicking
+        // when `parse()` returns an error.
+        let x: i64 = s.parse().unwrap();
+        Self::new(x).map_err(ParsePosNonzeroError::from_creation)
+    }
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn test_parse_error() {
+        assert!(matches!(
+            PositiveNonzeroInteger::parse("not a number"),
+            Err(ParsePosNonzeroError::ParseInt(_)),
+        ));
+    }
+
+    #[test]
+    fn test_negative() {
+        assert_eq!(
+            PositiveNonzeroInteger::parse("-555"),
+            Err(ParsePosNonzeroError::Creation(CreationError::Negative)),
+        );
+    }
+
+    #[test]
+    fn test_zero() {
+        assert_eq!(
+            PositiveNonzeroInteger::parse("0"),
+            Err(ParsePosNonzeroError::Creation(CreationError::Zero)),
+        );
+    }
+
+    #[test]
+    fn test_positive() {
+        let x = PositiveNonzeroInteger::new(42).unwrap();
+        assert_eq!(x.0, 42);
+        assert_eq!(PositiveNonzeroInteger::parse("42"), Ok(x));
+    }
+}

exercises/14_generics/README.md

@@ -1,11 +1,11 @@
 # Generics
 
 Generics is the topic of generalizing types and functionalities to broader cases.
-This is extremely useful for reducing code duplication in many ways, but can call for rather involving syntax.
+This is extremely useful for reducing code duplication in many ways, but can call for some rather involved syntax.
 Namely, being generic requires taking great care to specify over which types a generic type is actually considered valid.
 The simplest and most common use of generics is for type parameters.
 
 ## Further information
 
-- [Generic Data Types](https://doc.rust-lang.org/stable/book/ch10-01-syntax.html)
+- [Generic Data Types](https://doc.rust-lang.org/book/ch10-01-syntax.html)
 - [Bounds](https://doc.rust-lang.org/rust-by-example/generics/bounds.html)

exercises/14_generics/generics1.rs

@@ -0,0 +1,18 @@
+// `Vec<T>` is generic over the type `T`. In most cases, the compiler is able to
+// infer `T`, for example after pushing a value with a concrete type to the vector.
+// But in this exercise, the compiler needs some help through a type annotation.
+
+fn main() {
+    // TODO: Fix the compiler error by annotating the type of the vector
+    // `Vec<T>`. Choose `T` as some integer type that can be created from
+    // `u8` and `i8`.
+    let mut numbers = Vec::new();
+
+    // Don't change the lines below.
+    let n1: u8 = 42;
+    numbers.push(n1.into());
+    let n2: i8 = -1;
+    numbers.push(n2.into());
+
+    println!("{numbers:?}");
+}

exercises/14_generics/generics2.rs

@@ -1,20 +1,20 @@
 // This powerful wrapper provides the ability to store a positive integer value.
-// Rewrite it using generics so that it supports wrapping ANY type.
-
-// Execute `rustlings hint generics2` for hints!
-
-// I AM NOT DONE
-
+// TODO: Rewrite it using a generic so that it supports wrapping ANY type.
 struct Wrapper {
     value: u32,
 }
 
+// TODO: Adapt the struct's implementation to be generic over the wrapped value.
 impl Wrapper {
-    pub fn new(value: u32) -> Self {
+    fn new(value: u32) -> Self {
         Wrapper { value }
     }
 }
 
+fn main() {
+    // You can optionally experiment here.
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;

exercises/15_traits/README.md

@@ -7,13 +7,13 @@ Data types can implement traits. To do so, the methods making up the trait are d
 In this way, traits are somewhat similar to Java interfaces and C++ abstract classes.
 
 Some additional common Rust traits include:
+
 - `Clone` (the `clone` method)
 - `Display` (which allows formatted display via `{}`)
 - `Debug` (which allows formatted display via `{:?}`)
 
 Because traits indicate shared behavior between data types, they are useful when writing generics.
 
-
 ## Further information
 
 - [Traits](https://doc.rust-lang.org/book/ch10-02-traits.html)

exercises/15_traits/traits1.rs

@@ -0,0 +1,30 @@
+// The trait `AppendBar` has only one function which appends "Bar" to any object
+// implementing this trait.
+trait AppendBar {
+    fn append_bar(self) -> Self;
+}
+
+impl AppendBar for String {
+    // TODO: Implement `AppendBar` for the type `String`.
+}
+
+fn main() {
+    let s = String::from("Foo");
+    let s = s.append_bar();
+    println!("s: {s}");
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn is_foo_bar() {
+        assert_eq!(String::from("Foo").append_bar(), "FooBar");
+    }
+
+    #[test]
+    fn is_bar_bar() {
+        assert_eq!(String::from("").append_bar().append_bar(), "BarBar");
+    }
+}

exercises/15_traits/traits2.rs

@@ -0,0 +1,22 @@
+trait AppendBar {
+    fn append_bar(self) -> Self;
+}
+
+// TODO: Implement the trait `AppendBar` for a vector of strings.
+// `append_bar` should push the string "Bar" into the vector.
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn is_vec_pop_eq_bar() {
+        let mut foo = vec![String::from("Foo")].append_bar();
+        assert_eq!(foo.pop().unwrap(), "Bar");
+        assert_eq!(foo.pop().unwrap(), "Foo");
+    }
+}

exercises/15_traits/traits3.rs

@@ -0,0 +1,38 @@
+trait Licensed {
+    // TODO: Add a default implementation for `licensing_info` so that
+    // implementors like the two structs below can share that default behavior
+    // without repeating the function.
+    // The default license information should be the string "Default license".
+    fn licensing_info(&self) -> String;
+}
+
+struct SomeSoftware {
+    version_number: i32,
+}
+
+struct OtherSoftware {
+    version_number: String,
+}
+
+impl Licensed for SomeSoftware {} // Don't edit this line.
+impl Licensed for OtherSoftware {} // Don't edit this line.
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn is_licensing_info_the_same() {
+        let licensing_info = "Default license";
+        let some_software = SomeSoftware { version_number: 1 };
+        let other_software = OtherSoftware {
+            version_number: "v2.0.0".to_string(),
+        };
+        assert_eq!(some_software.licensing_info(), licensing_info);
+        assert_eq!(other_software.licensing_info(), licensing_info);
+    }
+}

exercises/15_traits/traits4.rs

@@ -0,0 +1,35 @@
+trait Licensed {
+    fn licensing_info(&self) -> String {
+        "Default license".to_string()
+    }
+}
+
+struct SomeSoftware;
+struct OtherSoftware;
+
+impl Licensed for SomeSoftware {}
+impl Licensed for OtherSoftware {}
+
+// TODO: Fix the compiler error by only changing the signature of this function.
+fn compare_license_types(software1: ???, software2: ???) -> bool {
+    software1.licensing_info() == software2.licensing_info()
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn compare_license_information() {
+        assert!(compare_license_types(SomeSoftware, OtherSoftware));
+    }
+
+    #[test]
+    fn compare_license_information_backwards() {
+        assert!(compare_license_types(OtherSoftware, SomeSoftware));
+    }
+}

exercises/15_traits/traits5.rs

@@ -0,0 +1,39 @@
+trait SomeTrait {
+    fn some_function(&self) -> bool {
+        true
+    }
+}
+
+trait OtherTrait {
+    fn other_function(&self) -> bool {
+        true
+    }
+}
+
+struct SomeStruct;
+impl SomeTrait for SomeStruct {}
+impl OtherTrait for SomeStruct {}
+
+struct OtherStruct;
+impl SomeTrait for OtherStruct {}
+impl OtherTrait for OtherStruct {}
+
+// TODO: Fix the compiler error by only changing the signature of this function.
+fn some_func(item: ???) -> bool {
+    item.some_function() && item.other_function()
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_some_func() {
+        assert!(some_func(SomeStruct));
+        assert!(some_func(OtherStruct));
+    }
+}

exercises/16_lifetimes/README.md

@@ -0,0 +1,22 @@
+# Lifetimes
+
+Lifetimes tell the compiler how to check whether references live long
+enough to be valid in any given situation. For example lifetimes say
+"make sure parameter 'a' lives as long as parameter 'b' so that the return
+value is valid".
+
+They are only necessary on borrows, i.e. references,
+since copied parameters or moves are owned in their scope and cannot
+be referenced outside. Lifetimes mean that calling code of e.g. functions
+can be checked to make sure their arguments are valid. Lifetimes are
+restrictive of their callers.
+
+If you'd like to learn more about lifetime annotations, the
+[lifetimekata](https://tfpk.github.io/lifetimekata/) project
+has a similar style of exercises to Rustlings, but is all about
+learning to write lifetime annotations.
+
+## Further information
+
+- [Lifetimes (in Rust By Example)](https://doc.rust-lang.org/stable/rust-by-example/scope/lifetime.html)
+- [Validating References with Lifetimes](https://doc.rust-lang.org/book/ch10-03-lifetime-syntax.html)

exercises/16_lifetimes/lifetimes1.rs

@@ -0,0 +1,28 @@
+// The Rust compiler needs to know how to check whether supplied references are
+// valid, so that it can let the programmer know if a reference is at risk of
+// going out of scope before it is used. Remember, references are borrows and do
+// not own their own data. What if their owner goes out of scope?
+
+// TODO: Fix the compiler error by updating the function signature.
+fn longest(x: &str, y: &str) -> &str {
+    if x.len() > y.len() {
+        x
+    } else {
+        y
+    }
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_longest() {
+        assert_eq!(longest("abcd", "123"), "abcd");
+        assert_eq!(longest("abc", "1234"), "1234");
+    }
+}

exercises/16_lifetimes/lifetimes2.rs

@@ -0,0 +1,20 @@
+// Don't change this function.
+fn longest<'a>(x: &'a str, y: &'a str) -> &'a str {
+    if x.len() > y.len() {
+        x
+    } else {
+        y
+    }
+}
+
+fn main() {
+    // TODO: Fix the compiler error by moving one line.
+
+    let string1 = String::from("long string is long");
+    let result;
+    {
+        let string2 = String::from("xyz");
+        result = longest(&string1, &string2);
+    }
+    println!("The longest string is '{result}'");
+}