Retro68/gcc/libgo/go/unicode/graphic.go

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2012-03-27 23:13:14 +00:00
// Copyright 2011 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 unicode
// Bit masks for each code point under U+0100, for fast lookup.
const (
pC = 1 << iota // a control character.
pP // a punctuation character.
pN // a numeral.
pS // a symbolic character.
pZ // a spacing character.
pLu // an upper-case letter.
pLl // a lower-case letter.
pp // a printable character according to Go's definition.
pg = pp | pZ // a graphical character according to the Unicode definition.
)
// GraphicRanges defines the set of graphic characters according to Unicode.
var GraphicRanges = []*RangeTable{
L, M, N, P, S, Zs,
}
// PrintRanges defines the set of printable characters according to Go.
// ASCII space, U+0020, is handled separately.
var PrintRanges = []*RangeTable{
L, M, N, P, S,
}
// IsGraphic reports whether the rune is defined as a Graphic by Unicode.
// Such characters include letters, marks, numbers, punctuation, symbols, and
// spaces, from categories L, M, N, P, S, Zs.
func IsGraphic(r rune) bool {
// We convert to uint32 to avoid the extra test for negative,
// and in the index we convert to uint8 to avoid the range check.
if uint32(r) <= MaxLatin1 {
return properties[uint8(r)]&pg != 0
}
return IsOneOf(GraphicRanges, r)
}
// IsPrint reports whether the rune is defined as printable by Go. Such
// characters include letters, marks, numbers, punctuation, symbols, and the
// ASCII space character, from categories L, M, N, P, S and the ASCII space
// character. This categorization is the same as IsGraphic except that the
// only spacing character is ASCII space, U+0020.
func IsPrint(r rune) bool {
if uint32(r) <= MaxLatin1 {
return properties[uint8(r)]&pp != 0
}
return IsOneOf(PrintRanges, r)
}
// IsOneOf reports whether the rune is a member of one of the ranges.
func IsOneOf(set []*RangeTable, r rune) bool {
for _, inside := range set {
if Is(inside, r) {
return true
}
}
return false
}
// IsControl reports whether the rune is a control character.
// The C (Other) Unicode category includes more code points
// such as surrogates; use Is(C, r) to test for them.
func IsControl(r rune) bool {
if uint32(r) <= MaxLatin1 {
return properties[uint8(r)]&pC != 0
}
// All control characters are < Latin1Max.
return false
}
// IsLetter reports whether the rune is a letter (category L).
func IsLetter(r rune) bool {
if uint32(r) <= MaxLatin1 {
return properties[uint8(r)]&(pLu|pLl) != 0
}
return Is(Letter, r)
}
// IsMark reports whether the rune is a mark character (category M).
func IsMark(r rune) bool {
// There are no mark characters in Latin-1.
return Is(Mark, r)
}
// IsNumber reports whether the rune is a number (category N).
func IsNumber(r rune) bool {
if uint32(r) <= MaxLatin1 {
return properties[uint8(r)]&pN != 0
}
return Is(Number, r)
}
// IsPunct reports whether the rune is a Unicode punctuation character
// (category P).
func IsPunct(r rune) bool {
if uint32(r) <= MaxLatin1 {
return properties[uint8(r)]&pP != 0
}
return Is(Punct, r)
}
// IsSpace reports whether the rune is a space character as defined
// by Unicode's White Space property; in the Latin-1 space
// this is
// '\t', '\n', '\v', '\f', '\r', ' ', U+0085 (NEL), U+00A0 (NBSP).
// Other definitions of spacing characters are set by category
// Z and property Pattern_White_Space.
func IsSpace(r rune) bool {
// This property isn't the same as Z; special-case it.
if uint32(r) <= MaxLatin1 {
switch r {
case '\t', '\n', '\v', '\f', '\r', ' ', 0x85, 0xA0:
return true
}
return false
}
return Is(White_Space, r)
}
// IsSymbol reports whether the rune is a symbolic character.
func IsSymbol(r rune) bool {
if uint32(r) <= MaxLatin1 {
return properties[uint8(r)]&pS != 0
}
return Is(Symbol, r)
}