blob: 3cddbbdda8cabd338c0da8ff2602c7bff9e7b34b [file] [log] [blame]
// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package internal contains non-exported functionality that are used by
// packages in the text repository.
package internal // import "golang.org/x/text/internal"
import (
"sort"
"golang.org/x/text/language"
)
// SortTags sorts tags in place.
func SortTags(tags []language.Tag) {
sort.Sort(sorter(tags))
}
type sorter []language.Tag
func (s sorter) Len() int {
return len(s)
}
func (s sorter) Swap(i, j int) {
s[i], s[j] = s[j], s[i]
}
func (s sorter) Less(i, j int) bool {
return s[i].String() < s[j].String()
}
// UniqueTags sorts and filters duplicate tags in place and returns a slice with
// only unique tags.
func UniqueTags(tags []language.Tag) []language.Tag {
if len(tags) <= 1 {
return tags
}
SortTags(tags)
k := 0
for i := 1; i < len(tags); i++ {
if tags[k].String() < tags[i].String() {
k++
tags[k] = tags[i]
}
}
return tags[:k+1]
}