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26 lines
702 B
Go
26 lines
702 B
Go
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// Copyright (c) Tailscale Inc & AUTHORS
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// SPDX-License-Identifier: BSD-3-Clause
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// Package checkchange defines a utility for determining whether a value
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// has changed since the last time it was checked.
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package checkchange
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// EqualCloner is an interface for types that can be compared for equality
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// and can be cloned.
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type EqualCloner[T any] interface {
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Equal(T) bool
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Clone() T
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}
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// Update sets *old to a clone of new if they are not equal, returning whether
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// they were different.
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//
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// It only modifies *old if they are different. old must be non-nil.
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func Update[T EqualCloner[T]](old *T, new T) (changed bool) {
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if new.Equal(*old) {
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return false
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}
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*old = new.Clone()
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return true
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}
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