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// Copyright 2015 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// Package internal contains non-exported functionality that are used by
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// packages in the text repository.
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package internal // import "golang.org/x/text/internal"
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import (
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	"sort"
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	"golang.org/x/text/language"
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)
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// SortTags sorts tags in place.
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func SortTags(tags []language.Tag) {
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	sort.Sort(sorter(tags))
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}
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type sorter []language.Tag
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func (s sorter) Len() int {
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	return len(s)
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}
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func (s sorter) Swap(i, j int) {
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	s[i], s[j] = s[j], s[i]
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}
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func (s sorter) Less(i, j int) bool {
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	return s[i].String() < s[j].String()
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}
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// UniqueTags sorts and filters duplicate tags in place and returns a slice with
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// only unique tags.
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func UniqueTags(tags []language.Tag) []language.Tag {
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	if len(tags) <= 1 {
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		return tags
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	}
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	SortTags(tags)
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	k := 0
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	for i := 1; i < len(tags); i++ {
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		if tags[k].String() < tags[i].String() {
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			k++
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			tags[k] = tags[i]
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		}
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	}
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	return tags[:k+1]
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}
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