Introduction

Ccloxx is a toy interpreter for the Lox language specified in Bob Nystrom's amazing book Crafting Interpreters. I writed this as an exercise following the book, so it's probably not production-quality code.

Compilation requires a C++11-compliant compiler.

cmake .
make

Ccloxx supports dynamic typing, lexical scope, control flow, and functions. For example:

// ccloxx ./UserScripts/fibonacci.lox
fun fibonacci(n) {
    if (n <= 1) return n;
    return fibonacci(n - 2) + fibonacci(n - 1);
}

for (var i = 0; i < 20; i = i + 1) {
    print fibonacci(i);
}

Ccloxx alos supports functions as first class, which means we can use closure.

// ccloxx ./UserScripts/closure.lox
fun line_conf(a, b) {
    fun line(x) {
        return a*x + b;
    }
    return line;
}

var line1 = line_conf(1, 1);
var line2 = line_conf(4, 5);
print line1(5); // "6".
print line2(4); // "21".

For more details on Lox's syntax, check out the description in Bob's book.

Usage

Here are some examples in ./UserScripts. To run stuff interactively using a REPL, do

./loxx

Alternatively, execute source files like so

./loxx <your source filename>