/
result.go
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/
result.go
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// Copyright 2023-2024 Oliver Eikemeier. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// SPDX-License-Identifier: Apache-2.0
package async
// Result defines the interface for returning results from asynchronous operations.
// It encapsulates the final value or error from the operation.
type Result[R any] interface {
V() (R, error) // The V method returns the final value or an error.
Value() R // The Value method returns the final value.
Err() error // The Err method returns the error.
}
// valueResult is an implementation of [Result] that simply holds a value.
type valueResult[R any] struct {
value R
}
// V returns the stored value.
func (v valueResult[R]) V() (R, error) {
return v.value, nil
}
// Value returns the stored value.
func (v valueResult[R]) Value() R {
return v.value
}
// The Err method returns nil.
func (v valueResult[R]) Err() error {
return nil
}
// errorResult handles errors from failed operations.
type errorResult[R any] struct {
err error
}
// V returns the stored error.
func (e errorResult[R]) V() (R, error) {
return *new(R), e.err
}
// Value returns the null value.
func (e errorResult[R]) Value() R {
return *new(R)
}
// Err returns the stored error.
func (e errorResult[R]) Err() error {
return e.err
}