BadgerScript

A toy language written in C.

Test with:

$ make
$ src/fh tests/mandelbrot.fh

Or, with Visual Studio on Windows:

> nmake -f Makefile.win
> fh tests\mandelbrot.fh

Features

• compilation to bytecode
• pretty fast register-based VM following Lua's design
• simple mark-and-sweep garbage collector
• full closures
• dynamic typing with null, boolean, number, string, array, map, closure (function), and c_func (C function) values

Status

Feature	Status
Parsing to AST	Working
Bytecode generation	Working
VM (bytecode execution)	Working
Garbage collection	Working
Closures	Working
Map and array objects	Working

Example Code

Closures

function make_counter(num) {
    return {
        "next" : function() {
            num = num + 1;
        },

        "read" : function() {
            return num;
        },
    };
}

function main() {
    var c1 = make_counter(0);
    var c2 = make_counter(10);
    c1.next();
    c2.next();
    printf("%d, %d\n", c1.read(), c2.read());    # prints 1, 11

    c1.next();
    if (c1.read() == 2 && c2.read() == 11) {
        printf("ok!\n");
    } else {
        error("this should will not happen");
    }
}

Mandelbrot Set

# check point c = (cx, cy) in the complex plane
function calc_point(cx, cy, max_iter)
{
    # start at the critical point z = (x, y) = 0
    var x = 0;
    var y = 0;

    var i = 0;
    while (i < max_iter) {
        # calculate next iteration: z = z^2 + c
        var t = x*x - y*y + cx;
        y = 2*x*y + cy;
        x = t;

        # stop if |z| > 2
        if (x*x + y*y > 4)
            break;
        i = i + 1;
    }
    return i;
}

function mandelbrot(x1, y1, x2, y2, size_x, size_y, max_iter)
{
    var step_x = (x2-x1) / (size_x-1);
    var step_y = (y2-y1) / (size_y-1);

    var y = y1;
    while (y <= y2) {
        var x = x1;
        while (x <= x2) {
            var n = calc_point(x, y, max_iter);
            if (n == max_iter)
                printf(".");         # in Mandelbrot set
            else
                printf("%d", n%10);  # outside
            x = x + step_x;
        }
        y = y + step_y;
        printf("\n");
    }
}

function main()
{
  mandelbrot(-2, -2, 2, 2, 150, 50, 1500);
}

License

MIT License (LICENSE)