mirror of
https://github.com/gohugoio/hugo.git
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47 lines
1.3 KiB
Go
47 lines
1.3 KiB
Go
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// Copyright 2024 The Hugo Authors. All rights reserved.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package hcontext
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import "context"
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// ContextDispatcher is a generic interface for setting and getting values from a context.
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type ContextDispatcher[T any] interface {
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Set(ctx context.Context, value T) context.Context
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Get(ctx context.Context) T
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}
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// NewContextDispatcher creates a new ContextDispatcher with the given key.
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func NewContextDispatcher[T any, R comparable](key R) ContextDispatcher[T] {
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return keyInContext[T, R]{
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id: key,
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}
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}
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type keyInContext[T any, R comparable] struct {
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zero T
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id R
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}
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func (f keyInContext[T, R]) Get(ctx context.Context) T {
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v := ctx.Value(f.id)
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if v == nil {
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return f.zero
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}
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return v.(T)
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}
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func (f keyInContext[T, R]) Set(ctx context.Context, value T) context.Context {
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return context.WithValue(ctx, f.id, value)
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}
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