comphash is a very lightweight Zig package offering a zero-cost compile-time hash map for immutable, O(1) string-keyed lookups without any runtime allocations.

Perfect for command‑line flag tables, protocol constant look‑ups, compile‑time DSLs, and any situation where the set of keys is known ahead of time.

✨ Features

🚀 Getting Started

Fetch via zig fetch

zig fetch --save git+https://github.com/galactixx/comphash#v0.1.0

This adds a comphash entry under .dependencies in your build.zig.zon.

Then in your build.zig:

const comphash_mod = b.dependency("comphash", .{
    .target = target,
    .optimize = optimize,
}).module("comphash");

// add to library
lib_mod.addImport("comphash", comphash_mod);

// add to executable
exe.root_module.addImport("comphash", comphash_mod);

This lets you const ch = @import("comphash"); in your Zig code.

📚 Usage

const std = @import("std");
const ch = @import("comphash");

const FruitMap = ch.ComptimeHashMap(u32, null, null, null);

pub fn main() !void {
    const kv = &.{ .{ "apple", 10 }, .{ "banana", 20 }, .{ "cherry", 30 } };
    const map = FruitMap.init(kv);

    std.debug.print("apple → {}\n", .{map.get("apple") orelse 0});
    std.debug.print("Length: {}\n",  .{map.length()});
}

🔍 API

ComptimeHashMap

pub fn ComptimeHashMap(
    comptime V:      type,                          // value type
    comptime hasher: ?fn([]const u8) u64,           // optional hash func
    comptime prober: ?Prober,                       // optional probe strategy
    comptime eql:    ?fn([]const u8,[]const u8)bool // optional equality
) type

Calling this generic returns a new struct type with the following notable members:

Prober

Enum controlling collision resolution:

• Linear – base + i
• DoubleHash – base + i * (h(key) | 1)
• Bidirectional – Alternates ±offsets
• Triangular – base + i * (i + 1) / 2

Select with the third parameter to ComptimeHashMap.

🤝 License

This project is licensed under the MIT License. See the LICENSE file for details.

📞 Contact & Contributing

Feel free to open an issue or a pull request. Discussion and feedback are welcome!