README.md

Ore

Thanks to Go 1.18, Now we can implement Option and Result like Rust!

Get Started

Option

You can use Option to express "nullable", just like all of the gophers did with pointer:

type Map[K comparable, V any] struct {
	inner map[K]V
}

func (mp *Map[K, V]) Get(key K) Option[V] {
	v, ok := mp.inner[key]
	if !ok {
		return None[V]()
	}

	return Some(v)
}

func main() {
    // init a Map

    if v := mp.Get("hello"); v.Some() {
        fmt.Println("we got value:", v.Value())
    } else {
        fmt.Println("failed to get value")
    }
}

Result

Result is "value or error":

func (mp *Map[K, V]) Get(key K) Result[V] {
	v, ok := mp.inner[key]
	if !ok {
		return mp.err(errors.New("key not found"))
	}

	return Ok(v)
}

func main() {
    // init a Map

    if res := mp.Get("hello"); res.IsErr() {
		fmt.Println("failed to get value of `hello`, err =", res.Err())
	} else {
		fmt.Println("value of `hello`:", res.Value())
	}
}

Refer to examples for more.