Overview
fddl is a small programming language inspired by various languages, designed to help learn language implementation concepts in Rust.
For years, I’ve tried to learn various programming languages, and while I could master the basics, the real-world projects often eluded me. And I wouldn't know who to turn to even if I knew where to start.
fddl was born out of this journey. fddl is my attempt to combine the aspects I appreciate from many languages into something uniquely my own.
I started learning Rust and have really liked it. I've been following tutorials and the Crafting Interpreters site as guides for this very problematic programming language.
I like aspects of so many programming languages, but I don't really like any of them, so I always found it hard to pick one and stick with it. But I had the same problem playing World of Warcraft, too.
So I, like many of you, decided to make a hobby programming language to see what may be able to be done with it. This is a brand new project as of September 2024 and I am one person.
The fact that I have a REPL working in this language is nothing short of amazing to me. It's fucking magic.
Features
- Custom syntax fddl introduces unique operators and keywords to make programming more intuitive and fun (at least for me)
- Lexer currently is the only thing working. It tokenizes fddl scripts into understandable pieces of the language.
- Tilde Operator (
~and~=) when something almost equals something else. I had the idea from watching a video on Non-Euclidean Doom.
Getting Started
Keep in mind, this is only at the lexer stage currently. It'll read your inputs and that's it.
To clone the repo:
git clone https://git.fddl.dev/fddl/fddl.gitTo run the REPL:
cargo runTo parse a fddl script:
cargo run path/to/script.fddlExamples:
func main() {
// print statement
print("hello, world in fddl");
// variable declaration
let y = 5;
// if statement
if (x > 10) {
print("x is greater than 10");
}
// while loop
while (x < 100) {
print(x);
let x = x + 1;
}
}At least for right now. I still want to do something odd.
Running the Project
Make sure your project compiles and the tests pass:
cargo build
cargo test
cargo runAgain, cargo run only starts the REPL for testing.
running fddl examples.fddl (from the git repo) produces the following.
Goals and Projections:
Note: This is not a final list; it's words on paper (metaphorically) at the time of writing.
Lexer:
- Built and tested for basic syntax and operators.
- Supports single-line and documentation comments.
- Add support for more complex syntax and features.
Parser:
- Working on building out functions to parse simple functionality in the language (if, while, for), and to read their expressions and values
- Implement parsing for function calls, expressions, checks, literally everything.
Compiler:
- Currently a placeholder. We're a long way from here. If I see this step I'll be lucky.
Comments:
- Added support for single-line and documentation comments.
- Implement multi-line comments.
- Implement document building comments.
Error Handling:
- Replace
stderrwith a more robust error handling mechanism..
Testing:
- Added initial
lexertests. - Expand tests to cover more syntax and edge cases.
License
This project is licensed under the MIT License.