...
Run Format

Source file src/bytes/bytes.go

     1	// Copyright 2009 The Go Authors. All rights reserved.
     2	// Use of this source code is governed by a BSD-style
     3	// license that can be found in the LICENSE file.
     4	
     5	// Package bytes implements functions for the manipulation of byte slices.
     6	// It is analogous to the facilities of the strings package.
     7	package bytes
     8	
     9	import (
    10		"unicode"
    11		"unicode/utf8"
    12	)
    13	
    14	func equalPortable(a, b []byte) bool {
    15		if len(a) != len(b) {
    16			return false
    17		}
    18		for i, c := range a {
    19			if c != b[i] {
    20				return false
    21			}
    22		}
    23		return true
    24	}
    25	
    26	// explode splits s into a slice of UTF-8 sequences, one per Unicode code point (still slices of bytes),
    27	// up to a maximum of n byte slices. Invalid UTF-8 sequences are chopped into individual bytes.
    28	func explode(s []byte, n int) [][]byte {
    29		if n <= 0 {
    30			n = len(s)
    31		}
    32		a := make([][]byte, n)
    33		var size int
    34		na := 0
    35		for len(s) > 0 {
    36			if na+1 >= n {
    37				a[na] = s
    38				na++
    39				break
    40			}
    41			_, size = utf8.DecodeRune(s)
    42			a[na] = s[0:size]
    43			s = s[size:]
    44			na++
    45		}
    46		return a[0:na]
    47	}
    48	
    49	// Count counts the number of non-overlapping instances of sep in s.
    50	// If sep is an empty slice, Count returns 1 + the number of Unicode code points in s.
    51	func Count(s, sep []byte) int {
    52		n := len(sep)
    53		if n == 0 {
    54			return utf8.RuneCount(s) + 1
    55		}
    56		if n > len(s) {
    57			return 0
    58		}
    59		count := 0
    60		c := sep[0]
    61		i := 0
    62		t := s[:len(s)-n+1]
    63		for i < len(t) {
    64			if t[i] != c {
    65				o := IndexByte(t[i:], c)
    66				if o < 0 {
    67					break
    68				}
    69				i += o
    70			}
    71			if n == 1 || Equal(s[i:i+n], sep) {
    72				count++
    73				i += n
    74				continue
    75			}
    76			i++
    77		}
    78		return count
    79	}
    80	
    81	// Contains reports whether subslice is within b.
    82	func Contains(b, subslice []byte) bool {
    83		return Index(b, subslice) != -1
    84	}
    85	
    86	// Index returns the index of the first instance of sep in s, or -1 if sep is not present in s.
    87	func Index(s, sep []byte) int {
    88		n := len(sep)
    89		if n == 0 {
    90			return 0
    91		}
    92		if n > len(s) {
    93			return -1
    94		}
    95		c := sep[0]
    96		if n == 1 {
    97			return IndexByte(s, c)
    98		}
    99		i := 0
   100		t := s[:len(s)-n+1]
   101		for i < len(t) {
   102			if t[i] != c {
   103				o := IndexByte(t[i:], c)
   104				if o < 0 {
   105					break
   106				}
   107				i += o
   108			}
   109			if Equal(s[i:i+n], sep) {
   110				return i
   111			}
   112			i++
   113		}
   114		return -1
   115	}
   116	
   117	func indexBytePortable(s []byte, c byte) int {
   118		for i, b := range s {
   119			if b == c {
   120				return i
   121			}
   122		}
   123		return -1
   124	}
   125	
   126	// LastIndex returns the index of the last instance of sep in s, or -1 if sep is not present in s.
   127	func LastIndex(s, sep []byte) int {
   128		n := len(sep)
   129		if n == 0 {
   130			return len(s)
   131		}
   132		c := sep[0]
   133		for i := len(s) - n; i >= 0; i-- {
   134			if s[i] == c && (n == 1 || Equal(s[i:i+n], sep)) {
   135				return i
   136			}
   137		}
   138		return -1
   139	}
   140	
   141	// LastIndexByte returns the index of the last instance of c in s, or -1 if c is not present in s.
   142	func LastIndexByte(s []byte, c byte) int {
   143		for i := len(s) - 1; i >= 0; i-- {
   144			if s[i] == c {
   145				return i
   146			}
   147		}
   148		return -1
   149	}
   150	
   151	// IndexRune interprets s as a sequence of UTF-8-encoded Unicode code points.
   152	// It returns the byte index of the first occurrence in s of the given rune.
   153	// It returns -1 if rune is not present in s.
   154	func IndexRune(s []byte, r rune) int {
   155		for i := 0; i < len(s); {
   156			r1, size := utf8.DecodeRune(s[i:])
   157			if r == r1 {
   158				return i
   159			}
   160			i += size
   161		}
   162		return -1
   163	}
   164	
   165	// IndexAny interprets s as a sequence of UTF-8-encoded Unicode code points.
   166	// It returns the byte index of the first occurrence in s of any of the Unicode
   167	// code points in chars.  It returns -1 if chars is empty or if there is no code
   168	// point in common.
   169	func IndexAny(s []byte, chars string) int {
   170		if len(chars) > 0 {
   171			var r rune
   172			var width int
   173			for i := 0; i < len(s); i += width {
   174				r = rune(s[i])
   175				if r < utf8.RuneSelf {
   176					width = 1
   177				} else {
   178					r, width = utf8.DecodeRune(s[i:])
   179				}
   180				for _, ch := range chars {
   181					if r == ch {
   182						return i
   183					}
   184				}
   185			}
   186		}
   187		return -1
   188	}
   189	
   190	// LastIndexAny interprets s as a sequence of UTF-8-encoded Unicode code
   191	// points.  It returns the byte index of the last occurrence in s of any of
   192	// the Unicode code points in chars.  It returns -1 if chars is empty or if
   193	// there is no code point in common.
   194	func LastIndexAny(s []byte, chars string) int {
   195		if len(chars) > 0 {
   196			for i := len(s); i > 0; {
   197				r, size := utf8.DecodeLastRune(s[0:i])
   198				i -= size
   199				for _, ch := range chars {
   200					if r == ch {
   201						return i
   202					}
   203				}
   204			}
   205		}
   206		return -1
   207	}
   208	
   209	// Generic split: splits after each instance of sep,
   210	// including sepSave bytes of sep in the subslices.
   211	func genSplit(s, sep []byte, sepSave, n int) [][]byte {
   212		if n == 0 {
   213			return nil
   214		}
   215		if len(sep) == 0 {
   216			return explode(s, n)
   217		}
   218		if n < 0 {
   219			n = Count(s, sep) + 1
   220		}
   221		c := sep[0]
   222		start := 0
   223		a := make([][]byte, n)
   224		na := 0
   225		for i := 0; i+len(sep) <= len(s) && na+1 < n; i++ {
   226			if s[i] == c && (len(sep) == 1 || Equal(s[i:i+len(sep)], sep)) {
   227				a[na] = s[start : i+sepSave]
   228				na++
   229				start = i + len(sep)
   230				i += len(sep) - 1
   231			}
   232		}
   233		a[na] = s[start:]
   234		return a[0 : na+1]
   235	}
   236	
   237	// SplitN slices s into subslices separated by sep and returns a slice of
   238	// the subslices between those separators.
   239	// If sep is empty, SplitN splits after each UTF-8 sequence.
   240	// The count determines the number of subslices to return:
   241	//   n > 0: at most n subslices; the last subslice will be the unsplit remainder.
   242	//   n == 0: the result is nil (zero subslices)
   243	//   n < 0: all subslices
   244	func SplitN(s, sep []byte, n int) [][]byte { return genSplit(s, sep, 0, n) }
   245	
   246	// SplitAfterN slices s into subslices after each instance of sep and
   247	// returns a slice of those subslices.
   248	// If sep is empty, SplitAfterN splits after each UTF-8 sequence.
   249	// The count determines the number of subslices to return:
   250	//   n > 0: at most n subslices; the last subslice will be the unsplit remainder.
   251	//   n == 0: the result is nil (zero subslices)
   252	//   n < 0: all subslices
   253	func SplitAfterN(s, sep []byte, n int) [][]byte {
   254		return genSplit(s, sep, len(sep), n)
   255	}
   256	
   257	// Split slices s into all subslices separated by sep and returns a slice of
   258	// the subslices between those separators.
   259	// If sep is empty, Split splits after each UTF-8 sequence.
   260	// It is equivalent to SplitN with a count of -1.
   261	func Split(s, sep []byte) [][]byte { return genSplit(s, sep, 0, -1) }
   262	
   263	// SplitAfter slices s into all subslices after each instance of sep and
   264	// returns a slice of those subslices.
   265	// If sep is empty, SplitAfter splits after each UTF-8 sequence.
   266	// It is equivalent to SplitAfterN with a count of -1.
   267	func SplitAfter(s, sep []byte) [][]byte {
   268		return genSplit(s, sep, len(sep), -1)
   269	}
   270	
   271	// Fields splits the slice s around each instance of one or more consecutive white space
   272	// characters, returning a slice of subslices of s or an empty list if s contains only white space.
   273	func Fields(s []byte) [][]byte {
   274		return FieldsFunc(s, unicode.IsSpace)
   275	}
   276	
   277	// FieldsFunc interprets s as a sequence of UTF-8-encoded Unicode code points.
   278	// It splits the slice s at each run of code points c satisfying f(c) and
   279	// returns a slice of subslices of s.  If all code points in s satisfy f(c), or
   280	// len(s) == 0, an empty slice is returned.
   281	// FieldsFunc makes no guarantees about the order in which it calls f(c).
   282	// If f does not return consistent results for a given c, FieldsFunc may crash.
   283	func FieldsFunc(s []byte, f func(rune) bool) [][]byte {
   284		n := 0
   285		inField := false
   286		for i := 0; i < len(s); {
   287			r, size := utf8.DecodeRune(s[i:])
   288			wasInField := inField
   289			inField = !f(r)
   290			if inField && !wasInField {
   291				n++
   292			}
   293			i += size
   294		}
   295	
   296		a := make([][]byte, n)
   297		na := 0
   298		fieldStart := -1
   299		for i := 0; i <= len(s) && na < n; {
   300			r, size := utf8.DecodeRune(s[i:])
   301			if fieldStart < 0 && size > 0 && !f(r) {
   302				fieldStart = i
   303				i += size
   304				continue
   305			}
   306			if fieldStart >= 0 && (size == 0 || f(r)) {
   307				a[na] = s[fieldStart:i]
   308				na++
   309				fieldStart = -1
   310			}
   311			if size == 0 {
   312				break
   313			}
   314			i += size
   315		}
   316		return a[0:na]
   317	}
   318	
   319	// Join concatenates the elements of s to create a new byte slice. The separator
   320	// sep is placed between elements in the resulting slice.
   321	func Join(s [][]byte, sep []byte) []byte {
   322		if len(s) == 0 {
   323			return []byte{}
   324		}
   325		if len(s) == 1 {
   326			// Just return a copy.
   327			return append([]byte(nil), s[0]...)
   328		}
   329		n := len(sep) * (len(s) - 1)
   330		for _, v := range s {
   331			n += len(v)
   332		}
   333	
   334		b := make([]byte, n)
   335		bp := copy(b, s[0])
   336		for _, v := range s[1:] {
   337			bp += copy(b[bp:], sep)
   338			bp += copy(b[bp:], v)
   339		}
   340		return b
   341	}
   342	
   343	// HasPrefix tests whether the byte slice s begins with prefix.
   344	func HasPrefix(s, prefix []byte) bool {
   345		return len(s) >= len(prefix) && Equal(s[0:len(prefix)], prefix)
   346	}
   347	
   348	// HasSuffix tests whether the byte slice s ends with suffix.
   349	func HasSuffix(s, suffix []byte) bool {
   350		return len(s) >= len(suffix) && Equal(s[len(s)-len(suffix):], suffix)
   351	}
   352	
   353	// Map returns a copy of the byte slice s with all its characters modified
   354	// according to the mapping function. If mapping returns a negative value, the character is
   355	// dropped from the string with no replacement.  The characters in s and the
   356	// output are interpreted as UTF-8-encoded Unicode code points.
   357	func Map(mapping func(r rune) rune, s []byte) []byte {
   358		// In the worst case, the slice can grow when mapped, making
   359		// things unpleasant.  But it's so rare we barge in assuming it's
   360		// fine.  It could also shrink but that falls out naturally.
   361		maxbytes := len(s) // length of b
   362		nbytes := 0        // number of bytes encoded in b
   363		b := make([]byte, maxbytes)
   364		for i := 0; i < len(s); {
   365			wid := 1
   366			r := rune(s[i])
   367			if r >= utf8.RuneSelf {
   368				r, wid = utf8.DecodeRune(s[i:])
   369			}
   370			r = mapping(r)
   371			if r >= 0 {
   372				rl := utf8.RuneLen(r)
   373				if rl < 0 {
   374					rl = len(string(utf8.RuneError))
   375				}
   376				if nbytes+rl > maxbytes {
   377					// Grow the buffer.
   378					maxbytes = maxbytes*2 + utf8.UTFMax
   379					nb := make([]byte, maxbytes)
   380					copy(nb, b[0:nbytes])
   381					b = nb
   382				}
   383				nbytes += utf8.EncodeRune(b[nbytes:maxbytes], r)
   384			}
   385			i += wid
   386		}
   387		return b[0:nbytes]
   388	}
   389	
   390	// Repeat returns a new byte slice consisting of count copies of b.
   391	func Repeat(b []byte, count int) []byte {
   392		nb := make([]byte, len(b)*count)
   393		bp := copy(nb, b)
   394		for bp < len(nb) {
   395			copy(nb[bp:], nb[:bp])
   396			bp *= 2
   397		}
   398		return nb
   399	}
   400	
   401	// ToUpper returns a copy of the byte slice s with all Unicode letters mapped to their upper case.
   402	func ToUpper(s []byte) []byte { return Map(unicode.ToUpper, s) }
   403	
   404	// ToLower returns a copy of the byte slice s with all Unicode letters mapped to their lower case.
   405	func ToLower(s []byte) []byte { return Map(unicode.ToLower, s) }
   406	
   407	// ToTitle returns a copy of the byte slice s with all Unicode letters mapped to their title case.
   408	func ToTitle(s []byte) []byte { return Map(unicode.ToTitle, s) }
   409	
   410	// ToUpperSpecial returns a copy of the byte slice s with all Unicode letters mapped to their
   411	// upper case, giving priority to the special casing rules.
   412	func ToUpperSpecial(_case unicode.SpecialCase, s []byte) []byte {
   413		return Map(func(r rune) rune { return _case.ToUpper(r) }, s)
   414	}
   415	
   416	// ToLowerSpecial returns a copy of the byte slice s with all Unicode letters mapped to their
   417	// lower case, giving priority to the special casing rules.
   418	func ToLowerSpecial(_case unicode.SpecialCase, s []byte) []byte {
   419		return Map(func(r rune) rune { return _case.ToLower(r) }, s)
   420	}
   421	
   422	// ToTitleSpecial returns a copy of the byte slice s with all Unicode letters mapped to their
   423	// title case, giving priority to the special casing rules.
   424	func ToTitleSpecial(_case unicode.SpecialCase, s []byte) []byte {
   425		return Map(func(r rune) rune { return _case.ToTitle(r) }, s)
   426	}
   427	
   428	// isSeparator reports whether the rune could mark a word boundary.
   429	// TODO: update when package unicode captures more of the properties.
   430	func isSeparator(r rune) bool {
   431		// ASCII alphanumerics and underscore are not separators
   432		if r <= 0x7F {
   433			switch {
   434			case '0' <= r && r <= '9':
   435				return false
   436			case 'a' <= r && r <= 'z':
   437				return false
   438			case 'A' <= r && r <= 'Z':
   439				return false
   440			case r == '_':
   441				return false
   442			}
   443			return true
   444		}
   445		// Letters and digits are not separators
   446		if unicode.IsLetter(r) || unicode.IsDigit(r) {
   447			return false
   448		}
   449		// Otherwise, all we can do for now is treat spaces as separators.
   450		return unicode.IsSpace(r)
   451	}
   452	
   453	// Title returns a copy of s with all Unicode letters that begin words
   454	// mapped to their title case.
   455	//
   456	// BUG(rsc): The rule Title uses for word boundaries does not handle Unicode punctuation properly.
   457	func Title(s []byte) []byte {
   458		// Use a closure here to remember state.
   459		// Hackish but effective. Depends on Map scanning in order and calling
   460		// the closure once per rune.
   461		prev := ' '
   462		return Map(
   463			func(r rune) rune {
   464				if isSeparator(prev) {
   465					prev = r
   466					return unicode.ToTitle(r)
   467				}
   468				prev = r
   469				return r
   470			},
   471			s)
   472	}
   473	
   474	// TrimLeftFunc returns a subslice of s by slicing off all leading UTF-8-encoded
   475	// Unicode code points c that satisfy f(c).
   476	func TrimLeftFunc(s []byte, f func(r rune) bool) []byte {
   477		i := indexFunc(s, f, false)
   478		if i == -1 {
   479			return nil
   480		}
   481		return s[i:]
   482	}
   483	
   484	// TrimRightFunc returns a subslice of s by slicing off all trailing UTF-8
   485	// encoded Unicode code points c that satisfy f(c).
   486	func TrimRightFunc(s []byte, f func(r rune) bool) []byte {
   487		i := lastIndexFunc(s, f, false)
   488		if i >= 0 && s[i] >= utf8.RuneSelf {
   489			_, wid := utf8.DecodeRune(s[i:])
   490			i += wid
   491		} else {
   492			i++
   493		}
   494		return s[0:i]
   495	}
   496	
   497	// TrimFunc returns a subslice of s by slicing off all leading and trailing
   498	// UTF-8-encoded Unicode code points c that satisfy f(c).
   499	func TrimFunc(s []byte, f func(r rune) bool) []byte {
   500		return TrimRightFunc(TrimLeftFunc(s, f), f)
   501	}
   502	
   503	// TrimPrefix returns s without the provided leading prefix string.
   504	// If s doesn't start with prefix, s is returned unchanged.
   505	func TrimPrefix(s, prefix []byte) []byte {
   506		if HasPrefix(s, prefix) {
   507			return s[len(prefix):]
   508		}
   509		return s
   510	}
   511	
   512	// TrimSuffix returns s without the provided trailing suffix string.
   513	// If s doesn't end with suffix, s is returned unchanged.
   514	func TrimSuffix(s, suffix []byte) []byte {
   515		if HasSuffix(s, suffix) {
   516			return s[:len(s)-len(suffix)]
   517		}
   518		return s
   519	}
   520	
   521	// IndexFunc interprets s as a sequence of UTF-8-encoded Unicode code points.
   522	// It returns the byte index in s of the first Unicode
   523	// code point satisfying f(c), or -1 if none do.
   524	func IndexFunc(s []byte, f func(r rune) bool) int {
   525		return indexFunc(s, f, true)
   526	}
   527	
   528	// LastIndexFunc interprets s as a sequence of UTF-8-encoded Unicode code points.
   529	// It returns the byte index in s of the last Unicode
   530	// code point satisfying f(c), or -1 if none do.
   531	func LastIndexFunc(s []byte, f func(r rune) bool) int {
   532		return lastIndexFunc(s, f, true)
   533	}
   534	
   535	// indexFunc is the same as IndexFunc except that if
   536	// truth==false, the sense of the predicate function is
   537	// inverted.
   538	func indexFunc(s []byte, f func(r rune) bool, truth bool) int {
   539		start := 0
   540		for start < len(s) {
   541			wid := 1
   542			r := rune(s[start])
   543			if r >= utf8.RuneSelf {
   544				r, wid = utf8.DecodeRune(s[start:])
   545			}
   546			if f(r) == truth {
   547				return start
   548			}
   549			start += wid
   550		}
   551		return -1
   552	}
   553	
   554	// lastIndexFunc is the same as LastIndexFunc except that if
   555	// truth==false, the sense of the predicate function is
   556	// inverted.
   557	func lastIndexFunc(s []byte, f func(r rune) bool, truth bool) int {
   558		for i := len(s); i > 0; {
   559			r, size := rune(s[i-1]), 1
   560			if r >= utf8.RuneSelf {
   561				r, size = utf8.DecodeLastRune(s[0:i])
   562			}
   563			i -= size
   564			if f(r) == truth {
   565				return i
   566			}
   567		}
   568		return -1
   569	}
   570	
   571	func makeCutsetFunc(cutset string) func(r rune) bool {
   572		return func(r rune) bool {
   573			for _, c := range cutset {
   574				if c == r {
   575					return true
   576				}
   577			}
   578			return false
   579		}
   580	}
   581	
   582	// Trim returns a subslice of s by slicing off all leading and
   583	// trailing UTF-8-encoded Unicode code points contained in cutset.
   584	func Trim(s []byte, cutset string) []byte {
   585		return TrimFunc(s, makeCutsetFunc(cutset))
   586	}
   587	
   588	// TrimLeft returns a subslice of s by slicing off all leading
   589	// UTF-8-encoded Unicode code points contained in cutset.
   590	func TrimLeft(s []byte, cutset string) []byte {
   591		return TrimLeftFunc(s, makeCutsetFunc(cutset))
   592	}
   593	
   594	// TrimRight returns a subslice of s by slicing off all trailing
   595	// UTF-8-encoded Unicode code points that are contained in cutset.
   596	func TrimRight(s []byte, cutset string) []byte {
   597		return TrimRightFunc(s, makeCutsetFunc(cutset))
   598	}
   599	
   600	// TrimSpace returns a subslice of s by slicing off all leading and
   601	// trailing white space, as defined by Unicode.
   602	func TrimSpace(s []byte) []byte {
   603		return TrimFunc(s, unicode.IsSpace)
   604	}
   605	
   606	// Runes returns a slice of runes (Unicode code points) equivalent to s.
   607	func Runes(s []byte) []rune {
   608		t := make([]rune, utf8.RuneCount(s))
   609		i := 0
   610		for len(s) > 0 {
   611			r, l := utf8.DecodeRune(s)
   612			t[i] = r
   613			i++
   614			s = s[l:]
   615		}
   616		return t
   617	}
   618	
   619	// Replace returns a copy of the slice s with the first n
   620	// non-overlapping instances of old replaced by new.
   621	// If old is empty, it matches at the beginning of the slice
   622	// and after each UTF-8 sequence, yielding up to k+1 replacements
   623	// for a k-rune slice.
   624	// If n < 0, there is no limit on the number of replacements.
   625	func Replace(s, old, new []byte, n int) []byte {
   626		m := 0
   627		if n != 0 {
   628			// Compute number of replacements.
   629			m = Count(s, old)
   630		}
   631		if m == 0 {
   632			// Just return a copy.
   633			return append([]byte(nil), s...)
   634		}
   635		if n < 0 || m < n {
   636			n = m
   637		}
   638	
   639		// Apply replacements to buffer.
   640		t := make([]byte, len(s)+n*(len(new)-len(old)))
   641		w := 0
   642		start := 0
   643		for i := 0; i < n; i++ {
   644			j := start
   645			if len(old) == 0 {
   646				if i > 0 {
   647					_, wid := utf8.DecodeRune(s[start:])
   648					j += wid
   649				}
   650			} else {
   651				j += Index(s[start:], old)
   652			}
   653			w += copy(t[w:], s[start:j])
   654			w += copy(t[w:], new)
   655			start = j + len(old)
   656		}
   657		w += copy(t[w:], s[start:])
   658		return t[0:w]
   659	}
   660	
   661	// EqualFold reports whether s and t, interpreted as UTF-8 strings,
   662	// are equal under Unicode case-folding.
   663	func EqualFold(s, t []byte) bool {
   664		for len(s) != 0 && len(t) != 0 {
   665			// Extract first rune from each.
   666			var sr, tr rune
   667			if s[0] < utf8.RuneSelf {
   668				sr, s = rune(s[0]), s[1:]
   669			} else {
   670				r, size := utf8.DecodeRune(s)
   671				sr, s = r, s[size:]
   672			}
   673			if t[0] < utf8.RuneSelf {
   674				tr, t = rune(t[0]), t[1:]
   675			} else {
   676				r, size := utf8.DecodeRune(t)
   677				tr, t = r, t[size:]
   678			}
   679	
   680			// If they match, keep going; if not, return false.
   681	
   682			// Easy case.
   683			if tr == sr {
   684				continue
   685			}
   686	
   687			// Make sr < tr to simplify what follows.
   688			if tr < sr {
   689				tr, sr = sr, tr
   690			}
   691			// Fast check for ASCII.
   692			if tr < utf8.RuneSelf && 'A' <= sr && sr <= 'Z' {
   693				// ASCII, and sr is upper case.  tr must be lower case.
   694				if tr == sr+'a'-'A' {
   695					continue
   696				}
   697				return false
   698			}
   699	
   700			// General case.  SimpleFold(x) returns the next equivalent rune > x
   701			// or wraps around to smaller values.
   702			r := unicode.SimpleFold(sr)
   703			for r != sr && r < tr {
   704				r = unicode.SimpleFold(r)
   705			}
   706			if r == tr {
   707				continue
   708			}
   709			return false
   710		}
   711	
   712		// One string is empty.  Are both?
   713		return len(s) == len(t)
   714	}
   715	

View as plain text