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path: root/src/pkg/bytes/bytes.go
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Diffstat (limited to 'src/pkg/bytes/bytes.go')
-rw-r--r--src/pkg/bytes/bytes.go697
1 files changed, 0 insertions, 697 deletions
diff --git a/src/pkg/bytes/bytes.go b/src/pkg/bytes/bytes.go
deleted file mode 100644
index 0c53e4c0b..000000000
--- a/src/pkg/bytes/bytes.go
+++ /dev/null
@@ -1,697 +0,0 @@
-// Copyright 2009 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 bytes implements functions for the manipulation of byte slices.
-// It is analogous to the facilities of the strings package.
-package bytes
-
-import (
- "unicode"
- "unicode/utf8"
-)
-
-func equalPortable(a, b []byte) bool {
- if len(a) != len(b) {
- return false
- }
- for i, c := range a {
- if c != b[i] {
- return false
- }
- }
- return true
-}
-
-// explode splits s into a slice of UTF-8 sequences, one per Unicode character (still slices of bytes),
-// up to a maximum of n byte slices. Invalid UTF-8 sequences are chopped into individual bytes.
-func explode(s []byte, n int) [][]byte {
- if n <= 0 {
- n = len(s)
- }
- a := make([][]byte, n)
- var size int
- na := 0
- for len(s) > 0 {
- if na+1 >= n {
- a[na] = s
- na++
- break
- }
- _, size = utf8.DecodeRune(s)
- a[na] = s[0:size]
- s = s[size:]
- na++
- }
- return a[0:na]
-}
-
-// Count counts the number of non-overlapping instances of sep in s.
-func Count(s, sep []byte) int {
- n := len(sep)
- if n == 0 {
- return utf8.RuneCount(s) + 1
- }
- if n > len(s) {
- return 0
- }
- count := 0
- c := sep[0]
- i := 0
- t := s[:len(s)-n+1]
- for i < len(t) {
- if t[i] != c {
- o := IndexByte(t[i:], c)
- if o < 0 {
- break
- }
- i += o
- }
- if n == 1 || Equal(s[i:i+n], sep) {
- count++
- i += n
- continue
- }
- i++
- }
- return count
-}
-
-// Contains reports whether subslice is within b.
-func Contains(b, subslice []byte) bool {
- return Index(b, subslice) != -1
-}
-
-// Index returns the index of the first instance of sep in s, or -1 if sep is not present in s.
-func Index(s, sep []byte) int {
- n := len(sep)
- if n == 0 {
- return 0
- }
- if n > len(s) {
- return -1
- }
- c := sep[0]
- if n == 1 {
- return IndexByte(s, c)
- }
- i := 0
- t := s[:len(s)-n+1]
- for i < len(t) {
- if t[i] != c {
- o := IndexByte(t[i:], c)
- if o < 0 {
- break
- }
- i += o
- }
- if Equal(s[i:i+n], sep) {
- return i
- }
- i++
- }
- return -1
-}
-
-func indexBytePortable(s []byte, c byte) int {
- for i, b := range s {
- if b == c {
- return i
- }
- }
- return -1
-}
-
-// LastIndex returns the index of the last instance of sep in s, or -1 if sep is not present in s.
-func LastIndex(s, sep []byte) int {
- n := len(sep)
- if n == 0 {
- return len(s)
- }
- c := sep[0]
- for i := len(s) - n; i >= 0; i-- {
- if s[i] == c && (n == 1 || Equal(s[i:i+n], sep)) {
- return i
- }
- }
- return -1
-}
-
-// IndexRune interprets s as a sequence of UTF-8-encoded Unicode code points.
-// It returns the byte index of the first occurrence in s of the given rune.
-// It returns -1 if rune is not present in s.
-func IndexRune(s []byte, r rune) int {
- for i := 0; i < len(s); {
- r1, size := utf8.DecodeRune(s[i:])
- if r == r1 {
- return i
- }
- i += size
- }
- return -1
-}
-
-// IndexAny interprets s as a sequence of UTF-8-encoded Unicode code points.
-// It returns the byte index of the first occurrence in s of any of the Unicode
-// code points in chars. It returns -1 if chars is empty or if there is no code
-// point in common.
-func IndexAny(s []byte, chars string) int {
- if len(chars) > 0 {
- var r rune
- var width int
- for i := 0; i < len(s); i += width {
- r = rune(s[i])
- if r < utf8.RuneSelf {
- width = 1
- } else {
- r, width = utf8.DecodeRune(s[i:])
- }
- for _, ch := range chars {
- if r == ch {
- return i
- }
- }
- }
- }
- return -1
-}
-
-// LastIndexAny interprets s as a sequence of UTF-8-encoded Unicode code
-// points. It returns the byte index of the last occurrence in s of any of
-// the Unicode code points in chars. It returns -1 if chars is empty or if
-// there is no code point in common.
-func LastIndexAny(s []byte, chars string) int {
- if len(chars) > 0 {
- for i := len(s); i > 0; {
- r, size := utf8.DecodeLastRune(s[0:i])
- i -= size
- for _, ch := range chars {
- if r == ch {
- return i
- }
- }
- }
- }
- return -1
-}
-
-// Generic split: splits after each instance of sep,
-// including sepSave bytes of sep in the subslices.
-func genSplit(s, sep []byte, sepSave, n int) [][]byte {
- if n == 0 {
- return nil
- }
- if len(sep) == 0 {
- return explode(s, n)
- }
- if n < 0 {
- n = Count(s, sep) + 1
- }
- c := sep[0]
- start := 0
- a := make([][]byte, n)
- na := 0
- for i := 0; i+len(sep) <= len(s) && na+1 < n; i++ {
- if s[i] == c && (len(sep) == 1 || Equal(s[i:i+len(sep)], sep)) {
- a[na] = s[start : i+sepSave]
- na++
- start = i + len(sep)
- i += len(sep) - 1
- }
- }
- a[na] = s[start:]
- return a[0 : na+1]
-}
-
-// SplitN slices s into subslices separated by sep and returns a slice of
-// the subslices between those separators.
-// If sep is empty, SplitN splits after each UTF-8 sequence.
-// The count determines the number of subslices to return:
-// n > 0: at most n subslices; the last subslice will be the unsplit remainder.
-// n == 0: the result is nil (zero subslices)
-// n < 0: all subslices
-func SplitN(s, sep []byte, n int) [][]byte { return genSplit(s, sep, 0, n) }
-
-// SplitAfterN slices s into subslices after each instance of sep and
-// returns a slice of those subslices.
-// If sep is empty, SplitAfterN splits after each UTF-8 sequence.
-// The count determines the number of subslices to return:
-// n > 0: at most n subslices; the last subslice will be the unsplit remainder.
-// n == 0: the result is nil (zero subslices)
-// n < 0: all subslices
-func SplitAfterN(s, sep []byte, n int) [][]byte {
- return genSplit(s, sep, len(sep), n)
-}
-
-// Split slices s into all subslices separated by sep and returns a slice of
-// the subslices between those separators.
-// If sep is empty, Split splits after each UTF-8 sequence.
-// It is equivalent to SplitN with a count of -1.
-func Split(s, sep []byte) [][]byte { return genSplit(s, sep, 0, -1) }
-
-// SplitAfter slices s into all subslices after each instance of sep and
-// returns a slice of those subslices.
-// If sep is empty, SplitAfter splits after each UTF-8 sequence.
-// It is equivalent to SplitAfterN with a count of -1.
-func SplitAfter(s, sep []byte) [][]byte {
- return genSplit(s, sep, len(sep), -1)
-}
-
-// Fields splits the slice s around each instance of one or more consecutive white space
-// characters, returning a slice of subslices of s or an empty list if s contains only white space.
-func Fields(s []byte) [][]byte {
- return FieldsFunc(s, unicode.IsSpace)
-}
-
-// FieldsFunc interprets s as a sequence of UTF-8-encoded Unicode code points.
-// It splits the slice s at each run of code points c satisfying f(c) and
-// returns a slice of subslices of s. If all code points in s satisfy f(c), or
-// len(s) == 0, an empty slice is returned.
-func FieldsFunc(s []byte, f func(rune) bool) [][]byte {
- n := 0
- inField := false
- for i := 0; i < len(s); {
- r, size := utf8.DecodeRune(s[i:])
- wasInField := inField
- inField = !f(r)
- if inField && !wasInField {
- n++
- }
- i += size
- }
-
- a := make([][]byte, n)
- na := 0
- fieldStart := -1
- for i := 0; i <= len(s) && na < n; {
- r, size := utf8.DecodeRune(s[i:])
- if fieldStart < 0 && size > 0 && !f(r) {
- fieldStart = i
- i += size
- continue
- }
- if fieldStart >= 0 && (size == 0 || f(r)) {
- a[na] = s[fieldStart:i]
- na++
- fieldStart = -1
- }
- if size == 0 {
- break
- }
- i += size
- }
- return a[0:na]
-}
-
-// Join concatenates the elements of s to create a new byte slice. The separator
-// sep is placed between elements in the resulting slice.
-func Join(s [][]byte, sep []byte) []byte {
- if len(s) == 0 {
- return []byte{}
- }
- if len(s) == 1 {
- // Just return a copy.
- return append([]byte(nil), s[0]...)
- }
- n := len(sep) * (len(s) - 1)
- for _, v := range s {
- n += len(v)
- }
-
- b := make([]byte, n)
- bp := copy(b, s[0])
- for _, v := range s[1:] {
- bp += copy(b[bp:], sep)
- bp += copy(b[bp:], v)
- }
- return b
-}
-
-// HasPrefix tests whether the byte slice s begins with prefix.
-func HasPrefix(s, prefix []byte) bool {
- return len(s) >= len(prefix) && Equal(s[0:len(prefix)], prefix)
-}
-
-// HasSuffix tests whether the byte slice s ends with suffix.
-func HasSuffix(s, suffix []byte) bool {
- return len(s) >= len(suffix) && Equal(s[len(s)-len(suffix):], suffix)
-}
-
-// Map returns a copy of the byte slice s with all its characters modified
-// according to the mapping function. If mapping returns a negative value, the character is
-// dropped from the string with no replacement. The characters in s and the
-// output are interpreted as UTF-8-encoded Unicode code points.
-func Map(mapping func(r rune) rune, s []byte) []byte {
- // In the worst case, the slice can grow when mapped, making
- // things unpleasant. But it's so rare we barge in assuming it's
- // fine. It could also shrink but that falls out naturally.
- maxbytes := len(s) // length of b
- nbytes := 0 // number of bytes encoded in b
- b := make([]byte, maxbytes)
- for i := 0; i < len(s); {
- wid := 1
- r := rune(s[i])
- if r >= utf8.RuneSelf {
- r, wid = utf8.DecodeRune(s[i:])
- }
- r = mapping(r)
- if r >= 0 {
- rl := utf8.RuneLen(r)
- if rl < 0 {
- rl = len(string(utf8.RuneError))
- }
- if nbytes+rl > maxbytes {
- // Grow the buffer.
- maxbytes = maxbytes*2 + utf8.UTFMax
- nb := make([]byte, maxbytes)
- copy(nb, b[0:nbytes])
- b = nb
- }
- nbytes += utf8.EncodeRune(b[nbytes:maxbytes], r)
- }
- i += wid
- }
- return b[0:nbytes]
-}
-
-// Repeat returns a new byte slice consisting of count copies of b.
-func Repeat(b []byte, count int) []byte {
- nb := make([]byte, len(b)*count)
- bp := 0
- for i := 0; i < count; i++ {
- bp += copy(nb[bp:], b)
- }
- return nb
-}
-
-// ToUpper returns a copy of the byte slice s with all Unicode letters mapped to their upper case.
-func ToUpper(s []byte) []byte { return Map(unicode.ToUpper, s) }
-
-// ToLower returns a copy of the byte slice s with all Unicode letters mapped to their lower case.
-func ToLower(s []byte) []byte { return Map(unicode.ToLower, s) }
-
-// ToTitle returns a copy of the byte slice s with all Unicode letters mapped to their title case.
-func ToTitle(s []byte) []byte { return Map(unicode.ToTitle, s) }
-
-// ToUpperSpecial returns a copy of the byte slice s with all Unicode letters mapped to their
-// upper case, giving priority to the special casing rules.
-func ToUpperSpecial(_case unicode.SpecialCase, s []byte) []byte {
- return Map(func(r rune) rune { return _case.ToUpper(r) }, s)
-}
-
-// ToLowerSpecial returns a copy of the byte slice s with all Unicode letters mapped to their
-// lower case, giving priority to the special casing rules.
-func ToLowerSpecial(_case unicode.SpecialCase, s []byte) []byte {
- return Map(func(r rune) rune { return _case.ToLower(r) }, s)
-}
-
-// ToTitleSpecial returns a copy of the byte slice s with all Unicode letters mapped to their
-// title case, giving priority to the special casing rules.
-func ToTitleSpecial(_case unicode.SpecialCase, s []byte) []byte {
- return Map(func(r rune) rune { return _case.ToTitle(r) }, s)
-}
-
-// isSeparator reports whether the rune could mark a word boundary.
-// TODO: update when package unicode captures more of the properties.
-func isSeparator(r rune) bool {
- // ASCII alphanumerics and underscore are not separators
- if r <= 0x7F {
- switch {
- case '0' <= r && r <= '9':
- return false
- case 'a' <= r && r <= 'z':
- return false
- case 'A' <= r && r <= 'Z':
- return false
- case r == '_':
- return false
- }
- return true
- }
- // Letters and digits are not separators
- if unicode.IsLetter(r) || unicode.IsDigit(r) {
- return false
- }
- // Otherwise, all we can do for now is treat spaces as separators.
- return unicode.IsSpace(r)
-}
-
-// Title returns a copy of s with all Unicode letters that begin words
-// mapped to their title case.
-//
-// BUG: The rule Title uses for word boundaries does not handle Unicode punctuation properly.
-func Title(s []byte) []byte {
- // Use a closure here to remember state.
- // Hackish but effective. Depends on Map scanning in order and calling
- // the closure once per rune.
- prev := ' '
- return Map(
- func(r rune) rune {
- if isSeparator(prev) {
- prev = r
- return unicode.ToTitle(r)
- }
- prev = r
- return r
- },
- s)
-}
-
-// TrimLeftFunc returns a subslice of s by slicing off all leading UTF-8-encoded
-// Unicode code points c that satisfy f(c).
-func TrimLeftFunc(s []byte, f func(r rune) bool) []byte {
- i := indexFunc(s, f, false)
- if i == -1 {
- return nil
- }
- return s[i:]
-}
-
-// TrimRightFunc returns a subslice of s by slicing off all trailing UTF-8
-// encoded Unicode code points c that satisfy f(c).
-func TrimRightFunc(s []byte, f func(r rune) bool) []byte {
- i := lastIndexFunc(s, f, false)
- if i >= 0 && s[i] >= utf8.RuneSelf {
- _, wid := utf8.DecodeRune(s[i:])
- i += wid
- } else {
- i++
- }
- return s[0:i]
-}
-
-// TrimFunc returns a subslice of s by slicing off all leading and trailing
-// UTF-8-encoded Unicode code points c that satisfy f(c).
-func TrimFunc(s []byte, f func(r rune) bool) []byte {
- return TrimRightFunc(TrimLeftFunc(s, f), f)
-}
-
-// TrimPrefix returns s without the provided leading prefix string.
-// If s doesn't start with prefix, s is returned unchanged.
-func TrimPrefix(s, prefix []byte) []byte {
- if HasPrefix(s, prefix) {
- return s[len(prefix):]
- }
- return s
-}
-
-// TrimSuffix returns s without the provided trailing suffix string.
-// If s doesn't end with suffix, s is returned unchanged.
-func TrimSuffix(s, suffix []byte) []byte {
- if HasSuffix(s, suffix) {
- return s[:len(s)-len(suffix)]
- }
- return s
-}
-
-// IndexFunc interprets s as a sequence of UTF-8-encoded Unicode code points.
-// It returns the byte index in s of the first Unicode
-// code point satisfying f(c), or -1 if none do.
-func IndexFunc(s []byte, f func(r rune) bool) int {
- return indexFunc(s, f, true)
-}
-
-// LastIndexFunc interprets s as a sequence of UTF-8-encoded Unicode code points.
-// It returns the byte index in s of the last Unicode
-// code point satisfying f(c), or -1 if none do.
-func LastIndexFunc(s []byte, f func(r rune) bool) int {
- return lastIndexFunc(s, f, true)
-}
-
-// indexFunc is the same as IndexFunc except that if
-// truth==false, the sense of the predicate function is
-// inverted.
-func indexFunc(s []byte, f func(r rune) bool, truth bool) int {
- start := 0
- for start < len(s) {
- wid := 1
- r := rune(s[start])
- if r >= utf8.RuneSelf {
- r, wid = utf8.DecodeRune(s[start:])
- }
- if f(r) == truth {
- return start
- }
- start += wid
- }
- return -1
-}
-
-// lastIndexFunc is the same as LastIndexFunc except that if
-// truth==false, the sense of the predicate function is
-// inverted.
-func lastIndexFunc(s []byte, f func(r rune) bool, truth bool) int {
- for i := len(s); i > 0; {
- r, size := rune(s[i-1]), 1
- if r >= utf8.RuneSelf {
- r, size = utf8.DecodeLastRune(s[0:i])
- }
- i -= size
- if f(r) == truth {
- return i
- }
- }
- return -1
-}
-
-func makeCutsetFunc(cutset string) func(r rune) bool {
- return func(r rune) bool {
- for _, c := range cutset {
- if c == r {
- return true
- }
- }
- return false
- }
-}
-
-// Trim returns a subslice of s by slicing off all leading and
-// trailing UTF-8-encoded Unicode code points contained in cutset.
-func Trim(s []byte, cutset string) []byte {
- return TrimFunc(s, makeCutsetFunc(cutset))
-}
-
-// TrimLeft returns a subslice of s by slicing off all leading
-// UTF-8-encoded Unicode code points contained in cutset.
-func TrimLeft(s []byte, cutset string) []byte {
- return TrimLeftFunc(s, makeCutsetFunc(cutset))
-}
-
-// TrimRight returns a subslice of s by slicing off all trailing
-// UTF-8-encoded Unicode code points that are contained in cutset.
-func TrimRight(s []byte, cutset string) []byte {
- return TrimRightFunc(s, makeCutsetFunc(cutset))
-}
-
-// TrimSpace returns a subslice of s by slicing off all leading and
-// trailing white space, as defined by Unicode.
-func TrimSpace(s []byte) []byte {
- return TrimFunc(s, unicode.IsSpace)
-}
-
-// Runes returns a slice of runes (Unicode code points) equivalent to s.
-func Runes(s []byte) []rune {
- t := make([]rune, utf8.RuneCount(s))
- i := 0
- for len(s) > 0 {
- r, l := utf8.DecodeRune(s)
- t[i] = r
- i++
- s = s[l:]
- }
- return t
-}
-
-// Replace returns a copy of the slice s with the first n
-// non-overlapping instances of old replaced by new.
-// If n < 0, there is no limit on the number of replacements.
-func Replace(s, old, new []byte, n int) []byte {
- m := 0
- if n != 0 {
- // Compute number of replacements.
- m = Count(s, old)
- }
- if m == 0 {
- // Just return a copy.
- return append([]byte(nil), s...)
- }
- if n < 0 || m < n {
- n = m
- }
-
- // Apply replacements to buffer.
- t := make([]byte, len(s)+n*(len(new)-len(old)))
- w := 0
- start := 0
- for i := 0; i < n; i++ {
- j := start
- if len(old) == 0 {
- if i > 0 {
- _, wid := utf8.DecodeRune(s[start:])
- j += wid
- }
- } else {
- j += Index(s[start:], old)
- }
- w += copy(t[w:], s[start:j])
- w += copy(t[w:], new)
- start = j + len(old)
- }
- w += copy(t[w:], s[start:])
- return t[0:w]
-}
-
-// EqualFold reports whether s and t, interpreted as UTF-8 strings,
-// are equal under Unicode case-folding.
-func EqualFold(s, t []byte) bool {
- for len(s) != 0 && len(t) != 0 {
- // Extract first rune from each.
- var sr, tr rune
- if s[0] < utf8.RuneSelf {
- sr, s = rune(s[0]), s[1:]
- } else {
- r, size := utf8.DecodeRune(s)
- sr, s = r, s[size:]
- }
- if t[0] < utf8.RuneSelf {
- tr, t = rune(t[0]), t[1:]
- } else {
- r, size := utf8.DecodeRune(t)
- tr, t = r, t[size:]
- }
-
- // If they match, keep going; if not, return false.
-
- // Easy case.
- if tr == sr {
- continue
- }
-
- // Make sr < tr to simplify what follows.
- if tr < sr {
- tr, sr = sr, tr
- }
- // Fast check for ASCII.
- if tr < utf8.RuneSelf && 'A' <= sr && sr <= 'Z' {
- // ASCII, and sr is upper case. tr must be lower case.
- if tr == sr+'a'-'A' {
- continue
- }
- return false
- }
-
- // General case. SimpleFold(x) returns the next equivalent rune > x
- // or wraps around to smaller values.
- r := unicode.SimpleFold(sr)
- for r != sr && r < tr {
- r = unicode.SimpleFold(r)
- }
- if r == tr {
- continue
- }
- return false
- }
-
- // One string is empty. Are both?
- return len(s) == len(t)
-}
generated by cgit v1.2.3 (git 2.39.1) at 2025-04-29 09:01:22 +0000