Merge pull request '108: Make pretty' (#275) from felixrabe/exercises:felixrabe-patch-6 into main

Reviewed-on: https://codeberg.org/ziglings/exercises/pulls/275

.gitea/issue_template.md

@@ -0,0 +1,5 @@
+Ziglings is a progressive learning series — each exercise builds on previous ones.
+Before opening an issue, please ensure you've followed the path and read the instructions carefully.
+
+Respectful and constructive feedback is always welcome.
+

README.md

@@ -45,7 +45,7 @@ Verify the installation and build number of `zig` like so:
 
 ```
 $ zig version
-0.14.0-dev.xxxx+xxxxxxxxx
+0.15.0-dev.xxxx+xxxxxxxxx
 ```
 
 Clone this repository with Git:
@@ -73,8 +73,8 @@ the appropriate tag.
 The Zig language is under very active development. In order to be
 current, Ziglings tracks **development** builds of the Zig
 compiler rather than versioned **release** builds. The last
-stable release was `0.13.0`, but Ziglings needs a dev build with
-pre-release version "0.14.0" and a build number at least as high
+stable release was `0.14.0`, but Ziglings needs a dev build with
+pre-release version "0.15.0" and a build number at least as high
 as that shown in the example version check above.
 
 It is likely that you'll download a build which is _greater_ than
@@ -233,6 +233,7 @@ Zig Core Language
 * [X] Interfaces
 * [X] Bit manipulation
 * [X] Working with C
+* [ ] Opaque types (anyopaque)
 * [X] Threading
 * [x] Labeled switch
 * [x] Vector operations (SIMD)

build.zig

@@ -200,7 +200,7 @@ pub fn build(b: *Build) !void {
 
     if (rand) |_| {
         // Random build mode: verifies one random exercise.
-        // like for 'exno' but chooses a random exersise number.
+        // like for 'exno' but chooses a random exercise number.
         print("work in progress: check a random exercise\n", .{});
 
         var prng = std.Random.DefaultPrng.init(blk: {
@@ -1146,7 +1146,7 @@ const exercises = [_]Exercise{
     },
     .{
         .main_file = "097_bit_manipulation.zig",
-        .output = "x = 0; y = 1",
+        .output = "x = 1011; y = 1101",
     },
     .{
         .main_file = "098_bit_manipulation2.zig",

exercises/033_iferror.zig

@@ -17,7 +17,7 @@
 //
 //     if (foo) |value| {
 //         ...
-//     } else |err| switch(err) {
+//     } else |err| switch (err) {
 //         ...
 //     }
 //

exercises/050_no_value.zig

@@ -43,7 +43,7 @@
 //
 //       "void" is a _type_, not a value. It is the most popular of the
 //       Zero Bit Types (those types which take up absolutely no space
-//       and have only a semantic value. When compiled to executable
+//       and have only a semantic value). When compiled to executable
 //       code, zero bit types generate no code at all. The above example
 //       shows a variable foo of type void which is assigned the value
 //       of an empty expression. It's much more common to see void as

exercises/071_comptime6.zig

@@ -7,7 +7,7 @@
 // doing this work.
 //
 // An 'inline for' is performed at compile time, allowing you to
-// programatically loop through a series of items in situations
+// programmatically loop through a series of items in situations
 // like those mentioned above where a regular runtime 'for' loop
 // wouldn't be allowed:
 //

exercises/082_anonymous_structs3.zig

@@ -95,13 +95,15 @@ fn printTuple(tuple: anytype) void {
         //     Each 'field' in this loop is one of these:
         //
         //         pub const StructField = struct {
-        //             name: []const u8,
+        //             name: [:0]const u8,
         //             type: type,
-        //             default_value: anytype,
+        //             default_value_ptr: ?*const anyopaque,
         //             is_comptime: bool,
         //             alignment: comptime_int,
         //         };
         //
+        //     Note we will learn about 'anyopaque' type later
+        //
         //     You'll need this builtin:
         //
         //         @field(lhs: anytype, comptime field_name: []const u8)

exercises/097_bit_manipulation.zig

@@ -71,9 +71,9 @@ const print = std.debug.print;
 
 pub fn main() !void {
 
-    // As in the example above, we use 1 and 0 as values for x and y
-    var x: u8 = 1;
-    var y: u8 = 0;
+    // Let us use 1101 and 1011 as values for x and y
+    var x: u8 = 0b1101;
+    var y: u8 = 0b1011;
 
     // Now we swap the values of the two variables by doing xor on them
     x ^= y;
@@ -82,7 +82,7 @@ pub fn main() !void {
     // What must be written here?
     ???;
 
-    print("x = {d}; y = {d}\n", .{ x, y });
+    print("x = {b}; y = {b}\n", .{ x, y });
 }
 
 // This variable swap takes advantage of the fact that the value resulting

exercises/105_threading2.zig

@@ -21,9 +21,9 @@
 // There were the Scottish mathematician Gregory and the German
 // mathematician Leibniz, and even a few hundred years earlier the Indian
 // mathematician Madhava. All of them independently developed the same
-// formula, which was published by Leibnitz in 1682 in the journal
+// formula, which was published by Leibniz in 1682 in the journal
 // "Acta Eruditorum".
-// This is why this method has become known as the "Leibnitz series",
+// This is why this method has become known as the "Leibniz series",
 // although the other names are also often used today.
 // We will not go into the formula and its derivation in detail, but
 // will deal with the series straight away:
@@ -50,7 +50,7 @@
 // enough for us for now, because we want to understand the principle and
 // nothing more, right?
 //
-// As we have already discovered, the Leibnitz series is a series with a
+// As we have already discovered, the Leibniz series is a series with a
 // fixed distance of 2 between the individual partial values. This makes
 // it easy to apply a simple loop to it, because if we start with n = 1
 // (which is not necessarily useful now) we always have to add 2 in each

exercises/107_files2.zig

@@ -12,7 +12,7 @@
 // Alright, bud, lean in close. Here's the game plan.
 //    - First, we open the {project_root}/output/ directory
 //    - Secondly, we open file `zigling.txt` in that directory
-//    - Then, we initalize an array of characters with all letter 'A', and print it
+//    - Then, we initialize an array of characters with all letter 'A', and print it
 //    - After that, we read the content of the file into the array
 //    - Finally, we print out the content we just read
 
@@ -30,9 +30,9 @@ pub fn main() !void {
     const file = try output_dir.openFile("zigling.txt", .{});
     defer file.close();
 
-    // initalize an array of u8 with all letter 'A'
+    // initialize an array of u8 with all letter 'A'
     // we need to pick the size of the array, 64 seems like a good number
-    // fix the initalization below
+    // fix the initialization below
     var content = ['A']*64;
     // this should print out : `AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA`
     std.debug.print("{s}\n", .{content});

exercises/108_labeled_switch.zig

@@ -19,12 +19,12 @@
 //              }
 //              break;
 //          }
-//      std.debug.print("This statement cannot be reached\n", .{});
+//          std.debug.print("This statement cannot be reached\n", .{});
 //      }
 //
-// By combining all we've learned so far, we can now proceed with a labeled switch
+// By combining all we've learned so far, we can now proceed with a labeled switch.
 //
-// A labeled switch is some extra syntatic sugar, which comes with all sorts of
+// A labeled switch is some extra syntactic sugar, which comes with all sorts of
 // candy (performance benefits). Don't believe me? Directly to source https://github.com/ziglang/zig/pull/21367
 //
 // Here is the previous excerpt implemented as a labeled switch instead:

exercises/110_quiz9.zig

@@ -161,7 +161,7 @@ pub fn main() !void {
 // In order to output a 1, the logic of an XOR operation requires that the
 // two input bits are of different values. Therefore, 0 ^ 1 and 1 ^ 0 will
 // both yield a 1 but 0 ^ 0 and 1 ^ 1 will output 0. XOR's unique behavior
-// of outputing a 0 when both inputs are 1s is what makes it different from
+// of outputting a 0 when both inputs are 1s is what makes it different from
 // the OR operator; it also gives us the ability to toggle bits by putting
 // 1s into our bitmask.
 //
@@ -247,7 +247,7 @@ pub fn main() !void {
 // PORTB = PORTB & 0b1011;
 // print("PORTB: {b:0>4}\n", .{PORTB}); // output -> 1010
 //
-// - 0s clear bits when used in conjuction with a bitwise AND.
+// - 0s clear bits when used in conjunction with a bitwise AND.
 // - 1s do nothing, thus preserving the original bits.
 //
 // -AND op- ---expanded---

patches/patches/082_anonymous_structs3.patch

@@ -1,5 +1,5 @@
---- exercises/082_anonymous_structs3.zig	2024-09-07 19:13:58.210327580 +0200
-+++ answers/082_anonymous_structs3.zig	2024-09-07 19:21:20.972733477 +0200
+--- exercises/082_anonymous_structs3.zig	2025-03-14 16:41:17.892873287 +0200
++++ answers/082_anonymous_structs3.zig	2025-03-14 16:40:56.043829543 +0200
 @@ -82,14 +82,14 @@
      //         @typeInfo(Circle).@"struct".fields
      //
@@ -17,7 +17,7 @@
          // 3. Print the field's name, type, and value.
          //
          //     Each 'field' in this loop is one of these:
-@@ -117,9 +117,9 @@
+@@ -119,9 +119,9 @@
          //
          // The first field should print as: "0"(bool):true
          print("\"{s}\"({any}):{any} ", .{

patches/patches/097_bit_manipulation.patch

@@ -1,5 +1,5 @@
---- exercises/097_bit_manipulation.zig	2023-10-03 22:15:22.125574535 +0200
-+++ answers/097_bit_manipulation.zig	2023-10-05 20:04:07.282771124 +0200
+--- exercises/097_bit_manipulation.zig	2025-05-12 21:25:03.395385743 +0200
++++ answers/097_bit_manipulation.zig	2025-05-12 21:22:57.472986976 +0200
 @@ -80,7 +80,7 @@
      y ^= x;
  
@@ -7,5 +7,5 @@
 -    ???;
 +    x ^= y;
  
-     print("x = {d}; y = {d}\n", .{ x, y });
+     print("x = {b}; y = {b}\n", .{ x, y });
  }

patches/patches/106_files.patch

@@ -1,63 +1,16 @@
---- exercises/106_files.zig	2024-11-09 20:33:07.455580904 +0100
-+++ answers/106_files.zig	2024-11-09 20:33:30.394785215 +0100
-@@ -1,22 +1,22 @@
- //
- // Until now, we've only been printing our output in the console,
--// which is good enough for fighting aliens and hermit bookkeeping.
-+// which is good enough for fighting alien and hermit bookkeeping.
- //
--// However, many other tasks require some interaction with the file system,
-+// However, many other task require some interaction with the file system,
- // which is the underlying structure for organizing files on your computer.
- //
--// The file system provides a hierarchical structure for storing files
--// by organizing them into directories, which hold files and other directories,
--// thus creating a tree structure that can be navigated.
-+// The File System provide a hierarchical structure for storing files
-+// by organizing files into directories, which hold files and other directories,
-+// thus creating a tree structure for navigating.
- //
--// Fortunately, the Zig Standard Library provides a simple API for interacting
--// with the file system, see the detail documentation here:
-+// Fortunately, the Zig Standard Library provide a simple api for interacting
-+// with the file system, see the detail documentation here
- //
- // https://ziglang.org/documentation/master/std/#std.fs
- //
--// In this exercise, we'll try to:
--//   - create a new directory,
--//   - open a file in the directory,
-+// In this exercise, we'll try to
-+//   - create a new directory
-+//   - open a file in the directory
- //   - write to the file.
- //
- // import std as always
-@@ -27,42 +27,42 @@
-     const cwd: std.fs.Dir = std.fs.cwd();
- 
-     // then we'll try to make a new directory /output/
--    // to store our output files.
-+    // to put our output files.
-     cwd.makeDir("output") catch |e| switch (e) {
--        // there is a chance you might want to run this
-+        // there are chance you might want to run this
-         // program more than once and the path might already
--        // have been created, so we'll have to handle this error
-+        // been created, so we'll have to handle this error
+--- exercises/106_files.zig	2025-03-13 15:26:59.532367792 +0200
++++ answers/106_files.zig	2025-03-14 22:04:52.243435159 +0200
+@@ -35,7 +35,7 @@
          // by doing nothing
          //
          // we want to catch error.PathAlreadyExists and do nothing
 -        ??? => {},
--        // if there's any other unexpected error we just propagate it through
 +        error.PathAlreadyExists => {},
-+        // if is any other unexpected error we just propagate it through
+         // if there's any other unexpected error we just propagate it through
          else => return e,
      };
- 
-     // then we'll try to open our freshly created directory
--    // wait a minute...
-+    // wait a minute
+@@ -44,7 +44,7 @@
+     // wait a minute...
      // opening a directory might fail!
      // what should we do here?
 -    var output_dir: std.fs.Dir = cwd.openDir("output", .{});
@@ -65,36 +18,12 @@
      defer output_dir.close();
  
      // we try to open the file `zigling.txt`,
--    // and propagate any error up
-+    // and propagate the error up if there are any errors
-     const file: std.fs.File = try output_dir.createFile("zigling.txt", .{});
-     // it is a good habit to close a file after you are done with it
-     // so that other programs can read it and prevent data corruption
+@@ -55,7 +55,7 @@
      // but here we are not yet done writing to the file
--    // if only there were a keyword in Zig that
--    // allowed you to "defer" code execution to the end of the scope...
+     // if only there were a keyword in Zig that
+     // allowed you to "defer" code execution to the end of the scope...
 -    file.close();
-+    // if only there were a keyword in zig that
-+    // allows you "defer" code execute to the end of scope...
 +    defer file.close();
  
--    // you are not allowed to move these two lines above the file closing line!
-+    // !you are not allowed to switch these two lines above the file closing line!
+     // you are not allowed to move these two lines above the file closing line!
      const byte_written = try file.write("It's zigling time!");
-     std.debug.print("Successfully wrote {d} bytes.\n", .{byte_written});
- }
- // to check if you actually write to the file, you can either,
--// 1. open the file in your text editor, or
-+// 1. open the file on your text editor, or
- // 2. print the content of the file in the console with the following command
- //    >> cat ./output/zigling.txt
- //
-@@ -86,7 +86,7 @@
- //
- // Question:
- //   - what should you do if you want to also read the file after opening it?
--//   - go to the documentation of the struct `std.fs.Dir` here:
-+//   - go to documentation of the struct `std.fs.Dir` here
- //     https://ziglang.org/documentation/master/std/#std.fs.Dir
- //       - can you find a function for opening a file? how about deleting a file?
- //       - what kind of options can you use with those functions?

patches/patches/107_files2.patch

@@ -1,55 +1,23 @@
---- exercises/107_files2.zig	2024-06-17 10:11:53.651439869 +0200
-+++ answers/107_files2.zig	2024-06-17 10:21:50.700671057 +0200
-@@ -4,17 +4,17 @@
- //    - create a file {project_root}/output/zigling.txt
- //      with content `It's zigling time!`(18 byte total)
- //
--// Now there's no point in writing to a file if we don't read from it, am I right?
--// Let's write a program to read the content of the file that we just created.
-+// Now there no point in writing to a file if we don't read from it am I right?
-+// let's write a program to read the content of the file that we just created.
- //
- // I am assuming that you've created the appropriate files for this to work.
- //
--// Alright, bud, lean in close. Here's the game plan.
-+// Alright, bud, lean in close here's the game plan.
- //    - First, we open the {project_root}/output/ directory
- //    - Secondly, we open file `zigling.txt` in that directory
--//    - Then, we initalize an array of characters with all letter 'A', and print it
--//    - After that, we read the content of the file into the array
--//    - Finally, we print out the content we just read
-+//    - then, we initalize an array of characters with all letter 'A', and print it
-+//    - After that, we read the content of the file to the array
-+//    - Finally, we print out the read content
- 
- const std = @import("std");
- 
-@@ -30,23 +30,23 @@
-     const file = try output_dir.openFile("zigling.txt", .{});
-     defer file.close();
- 
--    // initalize an array of u8 with all letter 'A'
--    // we need to pick the size of the array, 64 seems like a good number
-+    // initalize an array of u8 with all letter 'A'.
-+    // we need to pick the size of the array, 64 seems like a good number.
-     // fix the initalization below
+--- exercises/107_files2.zig	2025-03-13 15:26:59.532367792 +0200
++++ answers/107_files2.zig	2025-03-14 22:08:35.167953736 +0200
+@@ -33,7 +33,7 @@
+     // initialize an array of u8 with all letter 'A'
+     // we need to pick the size of the array, 64 seems like a good number
+     // fix the initialization below
 -    var content = ['A']*64;
 +    var content = [_]u8{'A'} ** 64;
      // this should print out : `AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA`
      std.debug.print("{s}\n", .{content});
  
-     // okay, seems like a threat of violence is not the answer in this case
--    // can you go here to find a way to read the content?
-+    // can you go here to find a way to read the content ?
+@@ -41,12 +41,12 @@
+     // can you go here to find a way to read the content?
      // https://ziglang.org/documentation/master/std/#std.fs.File
      // hint: you might find two answers that are both valid in this case
 -    const bytes_read = zig_read_the_file_or_i_will_fight_you(&content);
 +    const bytes_read = try file.read(&content);
  
--    // Woah, too screamy. I know you're excited for zigling time but tone it down a bit.
--    // Can you print only what we read from the file?
-+    // Woah, too screamy, I know you're excited for zigling time but tone it down a bit
-+    // Can you print only what we read from the file ?
+     // Woah, too screamy. I know you're excited for zigling time but tone it down a bit.
+     // Can you print only what we read from the file?
      std.debug.print("Successfully Read {d} bytes: {s}\n", .{
          bytes_read,
 -        content, // change this line only