bertzzie / javalox

Simple programming language implementation

Lox Interpreter

A simple implementation of Lox interpreter from the CraftingInterpreter book.

This is an exercise repo, meant to implement what's in the book with some addition:

• All challenges completed
• Better repl with syntax highlighting, etc
• Language Server to integrate with editors / IDE
• Static analysis tool

Building and Running

After cloning the repo, execute:

$ mvn package

to generate an executable jar in the target directory. You can then run the file:

$ java -jar target/lox-0.0.1-SNAPSHOT.jar

to see the REPL.

File and build system is not really supported for now, but the foundation to do so is there.

Current State

Right now the interpreter can:

• parse and execute basic statements (arithmetic, logical operation)
• assign global variable
• assign variable in block scope
• execute ternary operator
• flow control via if statement
• looping via for and while statements

More will come:

• Update REPL to support statement. Rule is: execute statement, print result of expression.

• Throws a runtime error on uninitialized variable

• Create an exact rule for global / local scoping, i.e.:

    var a = 1;
    {
      var a = a + 2;
      print a;
    }
  

  in C# this will give an error. C will prints 2 because that inside a counts as uninitialized and uninitialized is treated as null, and int + null is int.

• Integrate build and packaging system (maven? gradle?)

• Implement control flow (if, while, for)

• Implement break statement for looping

• Implement function and make sure it's first-class value

• Upgrade variable / function binding and resolving

• Implement Basic Class (OOP)

• Implement Inheritance

• Implmenet ADT

• Learn about VM and implement VM (likely in C or Rust)