Zig Result

This is a library for creating and using results (similar to the ones in Rust). Those results allows you to give more information about an error such as a description.

Zig Version: 0.13.0

Installation

You can either manually install the library, or automatically.

Manual

You can install the library by adding it to the build.zig.zon file, either manually like so:

.{
    ...
    .dependencies = .{
        .@"zig-result" = .{
            .url = "https://github.com/Remy2701/zig-result/archive/main.tar.gz",
            .hash = "...",
        }
    }
    ...
}

The hash can be found using the builtin command:

zig fetch https://github.com/Remy2701/zig-result/archive/main.tar.gz

Automatic

Or you can also add it automatically like so:

zig fetch --save https://github.com/Remy2701/zig-result/archive/main.tar.gz

Adding the module to your project

Then in the build.zig, you can add the following:

const zig_result = b.dependency("zig-result", .{
    .target = target,
    .optimize = optimize,
});

exe.root_module.addImport("result", zig_result.module("zig-result"));

The name of the module (result) can be changed to whatever you want.

Finally in your code you can import the module using the following:

const result = @import("result");

Example

const std = @import("std");
const Result = @import("result").Result;

pub fn main() !void {
    const ErrorPayload = union(enum) {
        InvalidCharacter: u8,
        Unknown: struct {
            message: []const u8,
        },
    };

    const ResultType = Result(i32, ErrorPayload);
    const result = ResultType.ok(42);

    const value = try result.unwrap();
    std.debug.print("value: {d}\n", .{value});

    unwrapCaptureExample: {
        var payload: ErrorPayload = undefined;
        _ = result2.unwrapCapture(&payload) catch |err| {
            std.debug.print("Error: {s} / {}\n", .{ @errorName(err), payload });
            break :unwrapCaptureExample;
        };
    }
}

More examples can be found in the tests, by navigating to the location of Result.