result

Result[T, E] for success or failure.

Rust API in Go

This is a wlrgo package. wlrgo ports Rust standard-library types to Go and intentionally copies the Rust API instead of reshaping it into an idiomatic Go design. Later packages in the org follow the same rule.

Names, combinators, and eager vs lazy evaluation follow std::result::Result as closely as Go generics allow. A few Go-only helpers exist where Rust has no equivalent: From, Get, GetErr, and Unpack.

Install

Requires Go 1.27 or later.

go get github.com/wlrgo/result/v2

Example

package main

import (
	"fmt"
	"strconv"

	"github.com/wlrgo/result/v2"
)

func main() {
	res := result.From(strconv.Atoi("2"))
	if v, ok := res.Get(); ok {
		fmt.Println(v)
	}

	fmt.Println(res.Map(func(n int) int { return n * 10 }).UnwrapOr(-1))
}

The zero value is Err. Ok and Err construct a result; From converts from (T, error). Combinators such as Map, And, and Or are methods. Compare, Flatten, and Collect remain package-level functions.

API

Group	Highlights
Query	IsOk, IsErr, IsOkAnd, IsErrAnd
Extract	Unwrap, Expect, UnwrapOr, Get
Combine	And, AndThen, Or, OrElse
Transform	Map, MapErr, Flatten, Inspect
Compare	Compare, Equal (Ok < Err)
Iterate	Seq, Collect
Convert	From, Get, GetErr, Unpack

See pkg.go.dev/github.com/wlrgo/result/v2 for the full API and package contract.

License

MIT