Lesser-Format

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A format utility for quick custom formatting in Zig. zig@0.15.2.

const Example = struct {
    a: u8,
    b: u16, // as hex
    c: bool, // skipped
    d: []u8, // str

    pub const format = formatWithHint(@This(), .{ .b = "0x{X}", .d = .str, .c = .skip});
};

API

• formatWithHint. Creates a fmt function, changing the behaviour of matching fields. Value args follow…
  • <fn> : calls the fn like a format procedure for that field.
  • <ptr> : assumption is a format string, concat and use.
  • .skip : skips and doesn’t print the field.
  • .skip_noted : skips printing out the value but still notes the existence of the field. E.g. .field_name = ⋯.
  • .str : Anything string like gets formatted with "{s}".
  • .fixed_c_str : C-like string that can be passed to std.mem.sliceTo(str, 0) prior to "{s}".
  • .flags : Prints out enabled fields in a flag struct (struct with just bool s). Skips non bool fields.
  • .unix_time : An int that is convertible into a std.posix.time_t, Print an 8601 like date-time. libc required.
• time8601Format. Prints out a 8601 like time-date from a Linux epoch. [2025-11-12T17:51:05]. libc required.
• flagsFormat. Prints out enabled fields in a flag struct (struct with just bool s). Skips non bool fields.
• HexDump. Prints out a formatted hex dump from the provided u8 slice.

Project Usage

Add to your build.zig.zon…

zig fetch --save git+https://codeberg.org/MinervasRefuge/Lesser-Format

Add to your build.zig…

const dependency_lesser_fmt = b.dependency("LesserFormat", .{
    .target = target,
    .optimize = optimise,
    .link_libc = true, // or `false` if time printing isn't needed
});
your_module.addImport("Lesser-Format", dependency_lesser_fmt.module("Lesser-Format"));

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BSD-3-Clause : Copyright © 2025 Abigale Raeck.