wren-zig

Wren bindings for zig!

Wren is a fast lua-sized scripting language with classes and concurrency.

Details on how embedding wren works here.

Bindings

In src/wren.zig

Contains both bare bindings and a zig wrapper

wrenGetSlotDouble(vm, 0);

vm.getSlotDouble(0);

Embedding

Recursively clone this repository and add the following to your build.zig, with the paths changed to match the correct location

const addWren = @import("wren-zig/build.zig").addWren;

pub fn build(b: *std.build.Builder) void {
    [...]
    const exe = b.addExecutable("wren-zig", "src/main.zig");
    addWren(exe);
    [...]
}

Example

A very basic example

const std = @import("std");
const wren = @import("wren");

pub fn main() anyerror!void {
    var config = wren.newConfig();
    config.write_fn = writeFn;
    config.error_fn = errorFn;
    var vm = wren.wrenNewVM(&config);
    defer vm.free();

    try vm.interpret("main", "System.print(\"Hello, world!\")");
}

pub export fn writeFn(vm: *wren.WrenVM, text: [*:0]const u8) void {
    _ = vm;
    const stdout = std.io.getStdOut().writer();
    stdout.print("{s}", .{ text }) catch unreachable;
}

pub export fn errorFn(vm: *wren.WrenVM, error_type: wren.WrenErrorType, module: [*:0]const u8, line: c_int, msg: [*:0]const u8) void {
    _ = vm;
    const stderr = std.io.getStdErr().writer();
    switch (error_type) {
        .WREN_ERROR_COMPILE => stderr.print("[{s} line {d}] [Error] {s}\n", .{ module, line, msg }) catch unreachable,
        .WREN_ERROR_STACK_TRACE => stderr.print("[{s} line {d}] in {s}\n", .{ module, line, msg }) catch unreachable,
        .WREN_ERROR_RUNTIME => stderr.print("[Runtime Error] {s}\n", .{ msg }) catch unreachable,
    }
}

See src/main.zig for more advanced use cases