+++
date = "2022-08-03"
tags = ["zig"]
title = "zigでcliを作る"
slug = "zig-cli"
+++

zigは、現時点で外部パッケージを読み込む機能がありません。rustならCargo.toml、rubyならGemfile、goならgo.modがあります。

zigには、いくつか有志が仕組みを作っていますが、決定的なものは存在しません。

- https://github.com/mattnite/gyro

- https://github.com/marler8997/zig-build-repos

したがって、build.zigにpathを書いていく必要があります。今回は、cli-toolを作ってみます。

```zig:build.zig
const std = @import("std");

pub fn build(b: *std.build.Builder) void {
    const mode = b.standardReleaseOptions();

    const lib = b.addStaticLibrary("zig-cli", "zig-cli/src/main.zig");
    lib.setBuildMode(mode);
    lib.install();

    const main_tests = b.addTest("zig-cli/src/tests.zig");
    main_tests.setBuildMode(mode);

    const test_step = b.step("test", "Run library tests");
    test_step.dependOn(&main_tests.step);

    const origin = b.addExecutable("random", "example/random.zig");
    origin.addPackagePath("zig-cli", "zig-cli/src/main.zig");
    origin.setBuildMode(mode);
    origin.install();

    b.default_step.dependOn(&origin.step);
}
```

https://github.com/sam701/zig-cli

```sh
$ git clone https://github.com/sam701/zig-cli
$ mkdir -p example
$ vim example/random.zig
```

```zig:example/random.zig
const std = @import("std");
const cli = @import("zig-cli");
const RndGen = std.rand.DefaultPrng;

var gpa = std.heap.GeneralPurposeAllocator(.{}){};
const allocator = gpa.allocator();

var app = &cli.Command{
    .name = "random",
    .help = "get random number",
    .action = run_server,
};

pub fn main() !void {
    return cli.run(app, allocator);
}

fn run_server(_: []const []const u8) !void {
    var rnd = RndGen.init(0);
    var some_random_num = rnd.random().int(i32);
    std.log.debug("{d}", .{some_random_num});
}
```

```sh
$ zig build
$ ./zig-out/bin/random
```

ref : https://www.reddit.com/r/Zig/comments/wc5rcb/hows_the_current_story_with_zig_in_terms_of/

ref : https://www.reddit.com/r/Zig/comments/wcvksf/what_is_missing_in_the_zig_ecosystem/