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23 lines
654 B
Go
23 lines
654 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 cmpx has code that will likely land in a future version of Go, but
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// we want sooner.
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package cmpx
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// Or returns the first non-zero element of list, or else returns the zero T.
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//
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// This is the proposal from
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// https://github.com/golang/go/issues/60204#issuecomment-1581245334.
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func Or[T comparable](list ...T) T {
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// TODO(bradfitz): remove the comparable constraint so we can use this
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// with funcs too and use reflect to see whether they're non-zero? 🤷♂️
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var zero T
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for _, v := range list {
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if v != zero {
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return v
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}
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}
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return zero
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}
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