mirror of
https://github.com/golang/go
synced 2024-11-07 18:46:14 -07:00
56 lines
1.1 KiB
Go
56 lines
1.1 KiB
Go
|
// run -gcflags=-G=3
|
||
|
|
||
|
// Copyright 2021 The Go Authors. All rights reserved.
|
||
|
// Use of this source code is governed by a BSD-style
|
||
|
// license that can be found in the LICENSE file.
|
||
|
|
||
|
package main
|
||
|
|
||
|
import (
|
||
|
"errors"
|
||
|
"fmt"
|
||
|
)
|
||
|
|
||
|
type Option[T any] struct {
|
||
|
ok bool
|
||
|
val T
|
||
|
}
|
||
|
|
||
|
func (o Option[T]) String() string {
|
||
|
if o.ok {
|
||
|
return fmt.Sprintf("Some(%v)", o.val)
|
||
|
}
|
||
|
return "None"
|
||
|
}
|
||
|
|
||
|
func Some[T any](val T) Option[T] { return Option[T]{ok: true, val: val} }
|
||
|
func None[T any]() Option[T] { return Option[T]{ok: false} }
|
||
|
|
||
|
type Result[T, E any] struct {
|
||
|
ok bool
|
||
|
val T
|
||
|
err E
|
||
|
}
|
||
|
|
||
|
func (r Result[T, E]) String() string {
|
||
|
if r.ok {
|
||
|
return fmt.Sprintf("Ok(%v)", r.val)
|
||
|
}
|
||
|
return fmt.Sprintf("Err(%v)", r.err)
|
||
|
}
|
||
|
|
||
|
func Ok[T, E any](val T) Result[T, E] { return Result[T, E]{ok: true, val: val} }
|
||
|
func Err[T, E any](err E) Result[T, E] { return Result[T, E]{ok: false, err: err} }
|
||
|
|
||
|
func main() {
|
||
|
a := Some[int](1)
|
||
|
b := None[int]()
|
||
|
fmt.Println(a, b)
|
||
|
|
||
|
x := Ok[int, error](1)
|
||
|
y := Err[int, error](errors.New("test"))
|
||
|
fmt.Println(x, y)
|
||
|
// fmt.Println(x)
|
||
|
_, _, _, _ = a, b, x, y
|
||
|
}
|