Mecha

A parser combinator library for the Zig programming language. Time to make your own parser mech!

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

const Rgb = struct {
    r: u8,
    g: u8,
    b: u8,
};

fn toByte(v: u4) u8 {
    return @as(u8, v) * 0x10 + v;
}

const hex1 = mecha.map(u8, toByte, mecha.int(u4, .{
    .parse_sign = false,
    .base = 16,
    .max_digits = 1,
}));
const hex2 = mecha.int(u8, .{
    .parse_sign = false,
    .base = 16,
    .max_digits = 2,
});
const rgb1 = mecha.map(Rgb, mecha.toStruct(Rgb), mecha.manyN(hex1, 3, .{}));
const rgb2 = mecha.map(Rgb, mecha.toStruct(Rgb), mecha.manyN(hex2, 3, .{}));
const rgb = mecha.combine(.{
    mecha.ascii.char('#'),
    mecha.oneOf(.{
        rgb2,
        rgb1,
    }),
});

test "rgb" {
    const testing = std.testing;
    const allocator = testing.allocator;
    const a = (try rgb(allocator, "#aabbcc")).value;
    try testing.expectEqual(@as(u8, 0xaa), a.r);
    try testing.expectEqual(@as(u8, 0xbb), a.g);
    try testing.expectEqual(@as(u8, 0xcc), a.b);

    const b = (try rgb(allocator, "#abc")).value;
    try testing.expectEqual(@as(u8, 0xaa), b.r);
    try testing.expectEqual(@as(u8, 0xbb), b.g);
    try testing.expectEqual(@as(u8, 0xcc), b.b);

    const c = (try rgb(allocator, "#000000")).value;
    try testing.expectEqual(@as(u8, 0), c.r);
    try testing.expectEqual(@as(u8, 0), c.g);
    try testing.expectEqual(@as(u8, 0), c.b);

    const d = (try rgb(allocator, "#000")).value;
    try testing.expectEqual(@as(u8, 0), d.r);
    try testing.expectEqual(@as(u8, 0), d.g);
    try testing.expectEqual(@as(u8, 0), d.b);
}

Package Contents

• example/rgb.zig
• example/json.zig
• example/README.md.template
• gyro.zzz
• .gitattributes
• mecha.zig
• LICENSE
• .github/workflows/ci.yml
• .github/dependabot.yml
• .github/FUNDING.yml
• build.zig
• src/ascii.zig
• src/utf8.zig
• README.md
• zig.mod
• .gitignore

History

	Published On	Tree @ Commit	Size
v0.4	Tue, 31 May 2022 08:09:48 UTC	Tree	82.362 KB
v0.3	Wed, 02 Mar 2022 16:55:39 UTC	Tree	82.357 KB
v0.2	Thu, 17 Feb 2022 14:59:09 UTC	Tree	82.365 KB
v0.1	Thu, 03 Feb 2022 20:53:48 UTC	Tree	82.299 KB