https://github.com/hejsil/mecha

A parser combinator library for Zig
https://github.com/hejsil/mecha

functional parser parser-combinators parser-library parsers zig zig-library zig-package

Last synced: about 10 hours ago
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A parser combinator library for Zig

• Host: GitHub
• URL: https://github.com/hejsil/mecha
• Owner: Hejsil
• License: mit
• Created: 2020-06-10T11:02:59.000Z (over 4 years ago)
• Default Branch: master
• Last Pushed: 2024-11-28T18:17:34.000Z (2 months ago)
• Last Synced: 2025-02-01T14:02:43.843Z (about 10 hours ago)
• Topics: functional, parser, parser-combinators, parser-library, parsers, zig, zig-library, zig-package
• Language: Zig
• Homepage:
• Size: 136 KB
• Stars: 505
• Watchers: 9
• Forks: 22
• Open Issues: 3
• Metadata Files:
  • Readme: README.md
  • Funding: .github/FUNDING.yml
  • License: LICENSE

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README

        
# Mecha

A parser combinator library for the [`Zig`](https://ziglang.org/)

programming language. Time to make your own parser mech!

![mech](https://thumbs.gfycat.com/GrippingElatedAzurevasesponge-size_restricted.gif)

```zig

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.int(u4, .{

    .parse_sign = false,

    .base = 16,

    .max_digits = 1,

}).map(toByte);

const hex2 = mecha.int(u8, .{

    .parse_sign = false,

    .base = 16,

    .max_digits = 2,

});

const rgb1 = mecha.manyN(hex1, 3, .{}).map(mecha.toStruct(Rgb));

const rgb2 = mecha.manyN(hex2, 3, .{}).map(mecha.toStruct(Rgb));

const rgb = mecha.combine(.{

    mecha.ascii.char('#').discard(),

    mecha.oneOf(.{ rgb2, rgb1 }),

});

test "rgb" {

    const testing = std.testing;

    const allocator = testing.allocator;

    const a = (try rgb.parse(allocator, "#aabbcc")).ok.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.parse(allocator, "#abc")).ok.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.parse(allocator, "#000000")).ok.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.parse(allocator, "#000")).ok.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);

}

```