Files
goutils/type/result.go

137 lines
2.4 KiB
Go

package Type
import (
"errors"
Assert "github.com/lbatuska/goutils/assert"
)
// CTORS BEGIN
func Ok[T any](value T) Result[T] {
return Result[T]{value: value, err: nil}
}
func Err[T any](err error) Result[T] {
return Result[T]{err: err}
}
func Err_t[T any](err error, x T) Result[T] {
return Result[T]{err: err}
}
// CTORS END
func (res *Result[T]) IsOk() bool {
if res == nil {
return false
}
return res.err == nil
}
func (res *Result[T]) IsErr() bool {
if res == nil {
return true
}
return res.err != nil
}
func (res *Result[T]) HasValue() bool {
if res == nil {
return false
}
return res.IsOk()
}
// UNWRAPPABLE INTERFACE
func (res *Result[T]) Expect(msg string) T {
Assert.NotNil(res)
if res.err == nil {
return res.value
}
panic(msg)
}
func (res *Result[T]) Unwrap() T {
Assert.NotNil(res)
if res.err == nil {
return res.value
}
panic("Tried unwrapping a Result that had an error value!")
}
func (res *Result[T]) UnwrapOr(val T) T {
if res != nil {
if res.err == nil {
return res.value
}
}
return val
}
func (res *Result[T]) UnwrapOrDefault() T {
if res != nil {
if res.err == nil {
return res.value
}
}
var ret T
return ret
}
func (res *Result[T]) UnwrapOrElse(f func() T) T {
if res != nil {
if res.err == nil {
return res.value
}
}
return f()
}
// UNWRAPPABLE INTERFACE
// This function panic on Ok instead of Err
func (res *Result[T]) ExpectErr(msg string) error {
if res == nil {
return errors.New("ExpectErr was called on a nil Result.")
}
if res.err != nil {
return res.err
}
panic(msg)
}
// This function panic on Ok instead of Err
func (res *Result[T]) UnwrapErr() error {
if res == nil {
return errors.New("UnwrapErr was called on a nil Result.")
}
if res.err != nil {
return res.err
}
panic("Expect_err was called with an Ok value")
}
// transforms Result into Option, mapping Ok(v) to Some(v) and Err(e) to None
func (res *Result[T]) Ok() Optional[T] {
if res != nil {
if res.err == nil {
return Optional[T]{value: res.value, present: true}
}
}
return Optional[T]{present: false}
}
// transforms Result into Option, mapping Err(e) to Some(e) and Ok(v) to None
func (res *Result[T]) Err() Optional[error] {
if res == nil {
return Optional[error]{
value: errors.New("Err was called on a nil Result."), present: true,
}
}
if res.err != nil {
return Optional[error]{value: res.err, present: true}
}
return Optional[error]{present: false}
}