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option.go
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option.go
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package rusty
import (
"errors"
)
type Option[T any] struct {
data *T
}
func ToOption[T any](data *T) *Option[T] {
return &Option[T]{
data: data,
}
}
func ToNone[T any]() *Option[T] {
return &Option[T]{}
}
func (o *Option[T]) Expect(message string) T {
if o.data == nil {
panic(errors.New(message))
}
return *o.data
}
func (o *Option[T]) Unwrap() T {
if o.data == nil {
panic("Option is nil")
}
return *o.data
}
func (o *Option[T]) UnwrapOr(value T) T {
if o.data == nil {
return value
}
return *o.data
}
func (o *Option[T]) UnwrapOrElse(fn func() T) T {
if o.data == nil {
return fn()
}
return *o.data
}
func (o *Option[T]) IsSome() bool {
if o.data == nil {
return false
}
return true
}
func (o *Option[T]) IsSomeWith(fn func(value T) bool) bool {
if o.data == nil {
return false
}
return fn(*o.data)
}
func (o *Option[T]) IsNone() bool {
return !o.IsSome()
}
func MapOption[T any, N any](option *Option[T], fn func(value T) N) *Option[N] {
if option.IsSome() {
data := fn(option.Unwrap())
return ToOption(&data)
}
return ToOption[N](nil)
}