leavez / go-optional

optional type for golang

go-optional

The optional type for golang, implemented with generics (go 1.18).

TLDR

var v optional.Type[int] = optional.New(123)
if unwrapped, ok := v.Value(); ok {
    unwrapped // 123
}

v.IsNil()      // false
v.ForceValue() // 123

Methods

initializer

• optional.New(XX)

If XX is nil, it returns Nil

• optional.Nil()
• (optional.FromPtr(XXX) returns optional.Nil() if pointer is nil)

value

• Value()

var v = optional.New(123)
if unwrapped, ok := v.Value(); ok {
    unwrapped // 123
}

• ForceValue()

• IsNil()

• ValueOrDefault(XX)

• ValueOrLazyDefault(f)

transform

• Map

optional.Map( optional.New(123), func(t int) string {
    return fmt.Sprintf("hello %d", t)
}) // optional.Type[string]

• Compact

var v = optional.New(optional.New(123))
optional.Compact(v) // optional.Type[int]

serialization

json Marshal and Umarshal supported.

If Nil, the encoded json data is null.

License

MIT