alexnask / ctregex.zig

Compile time regular expressions in zig

Zig compile time regular expressions

Generating fast code since 2020

Features

• Comptime regular expression compilation
• Comptime and runtime matching
• UTF8, UTF16le, ASCII, codepoint array support
• Captures (with named (:<name>...) support)
• |, *, +, ?, (:?...), [...], [^...], {N}, {min,}, {min,max}
• '\d', '\s' character classes

TODO

• Faster generated code using DFAs when possible
• search, findAll, etc.
• More character classes
• More features (backreferences etc.)

Example

test "runtime matching" {
    @setEvalBranchQuota(1250);
    // The encoding is utf8 by default, you can use .ascii, .utf16le, .codepoint here instead.
    if (try match("(?<test>def|abc)([😇ω])+", .{.encoding = .utf8}, "abc😇ωωωωω")) |res| {
        std.debug.warn("Test: {}, 1: {}\n", .{ res.capture("test"), res.captures[1] });
    }
}

test "comptime matching" {
    @setEvalBranchQuota(2700);
    if (comptime try match("(?<test>def|abc)([😇ω])+", .{}, "abc😇ωωωωω")) |res| {
        @compileError("Test: " ++ res.capture("test").? ++ ", 1: " ++ res.captures[1].?);
    }
}

See tests.zig for more examples.
Small benchmark with ctregex, PCRE2