route/vendor/golang.org/x/text/unicode/runenames/runenames.go

49 lines
1.2 KiB
Go

// Copyright 2016 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.
//go:generate go run gen.go gen_bits.go
// Package runenames provides rune names from the Unicode Character Database.
// For example, the name for '\u0100' is "LATIN CAPITAL LETTER A WITH MACRON".
//
// See http://www.unicode.org/Public/UCD/latest/ucd/UnicodeData.txt
package runenames
import (
"sort"
)
// Name returns the name for r.
func Name(r rune) string {
i := sort.Search(len(table0), func(j int) bool {
e := table0[j]
rOffset := rune(e >> shiftRuneOffset)
return r < rOffset
})
if i == 0 {
return ""
}
e := table0[i-1]
rOffset := rune(e >> shiftRuneOffset)
rLength := rune(e>>shiftRuneLength) & maskRuneLength
if r >= rOffset+rLength {
return ""
}
if (e>>shiftDirect)&maskDirect != 0 {
o := int(e>>shiftDataOffset) & maskDataOffset
n := int(e>>shiftDataLength) & maskDataLength
return data[o : o+n]
}
base := uint32(e>>shiftDataBase) & maskDataBase
base <<= dataBaseUnit
j := rune(e>>shiftTable1Offset) & maskTable1Offset
j += r - rOffset
d0 := base + uint32(table1[j-1]) // dataOffset
d1 := base + uint32(table1[j-0]) // dataOffset + dataLength
return data[d0:d1]
}