// Trim returns a slice of the string s, with all leading and trailing white space
// removed, as defined by Unicode.
func TrimSpace(s []byte) []byte {
start, end := 0, len(s)
for start < end {
wid := 1
rune := int(s[start])
if rune >= utf8.RuneSelf {
rune, wid = utf8.DecodeRune(s[start:end])
}
if !unicode.IsSpace(rune) {
break
}
start += wid
}
for start < end {
wid := 1
rune := int(s[end-1])
if rune >= utf8.RuneSelf {
// Back up carefully looking for beginning of rune. Mustn't pass start.
for wid = 2; start <= end-wid && !utf8.RuneStart(s[end-wid]); wid++ {
}
if start > end-wid { // invalid UTF-8 sequence; stop processing
return s[start:end]
}
rune, wid = utf8.DecodeRune(s[end-wid : end])
}
if !unicode.IsSpace(rune) {
break
}
end -= wid
}
return s[start:end]
}
// FieldsFunc interprets s as a sequence of UTF-8-encoded Unicode code points.
// It splits the array s at each run of code points c satisfying f(c) and
// returns a slice of subarrays of s. If no code points in s satisfy f(c), an
// empty slice is returned.
func FieldsFunc(s []byte, f func(int) bool) [][]byte {
n := 0
inField := false
for i := 0; i < len(s); {
rune, size := utf8.DecodeRune(s[i:])
wasInField := inField
inField = !f(rune)
if inField && !wasInField {
n++
}
i += size
}
a := make([][]byte, n)
na := 0
fieldStart := -1
for i := 0; i <= len(s) && na < n; {
rune, size := utf8.DecodeRune(s[i:])
if fieldStart < 0 && size > 0 && !f(rune) {
fieldStart = i
i += size
continue
}
if fieldStart >= 0 && (size == 0 || f(rune)) {
a[na] = s[fieldStart:i]
na++
fieldStart = -1
}
if size == 0 {
break
}
i += size
}
return a[0:na]
}
func (self *scanner) nextWord() (word tok, err os.Error) {
if self.index >= len(self.content) {
err = os.NewError("EOF")
return
}
for self.index < len(self.content) {
r, l := utf8.DecodeRune(self.content[self.index:])
if !unicode.IsSpace(r) || r == '\n' {
break
}
self.index += l
}
j, ttype, inchar, incode := self.index, other, false, 0
for self.index < len(self.content) {
r, l := utf8.DecodeRune(self.content[self.index:])
if r == '\'' {
inchar = !inchar
}
if self.index == j {
switch {
case unicode.IsUpper(r):
ttype = nonterm
case r == '\n':
self.index++
ttype = newline
break
case r == ':':
ttype = begindef
case r == ';':
ttype = enddef
case r == '|':
ttype = alternate
case r == '{' && memorizeTerms:
incode++
ttype = code
default:
ttype = term
}
} else if incode > 0 && r == '{' {
incode++
} else if incode > 0 && r == '}' {
incode--
}
if incode == 0 && !inchar && unicode.IsSpace(r) {
break
}
self.index += l
}
token := string(self.content[j:self.index])
if ttype == newline {
token = ""
}
word = tok{token, ttype}
return
}
// 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)
}
func (s inputBytes) hangul(p int) uint32 {
if !isHangul(s[p:]) {
return 0
}
rune, _ := utf8.DecodeRune(s[p:])
return uint32(rune)
}
// insert inserts the given rune in the buffer ordered by CCC.
// It returns true if the buffer was large enough to hold the decomposed rune.
func (rb *reorderBuffer) insert(src []byte, info runeInfo) bool {
if info.size == 3 && isHangul(src) {
rune, _ := utf8.DecodeRune(src)
return rb.decomposeHangul(uint32(rune))
}
if info.flags.hasDecomposition() {
dcomp := rb.f.decompose(src)
for i := 0; i < len(dcomp); {
info = rb.f.info(dcomp[i:])
pos := rb.nbyte
if !rb.insertOrdered(info) {
return false
}
end := i + int(info.size)
copy(rb.byte[pos:], dcomp[i:end])
i = end
}
} else {
pos := rb.nbyte
if !rb.insertOrdered(info) {
return false
}
copy(rb.byte[pos:], src[:info.size])
}
return true
}
func _peek_char(port Obj) Obj {
if is_immediate(port) {
panic("bad type")
}
switch v := (*port).(type) {
case *InputPort:
if v.is_binary {
panic("bad port type")
}
for !utf8.FullRune(v.lookahead[0:v.lookahead_valid]) {
n, err := io.ReadFull(v.r,
v.lookahead[v.lookahead_valid:v.lookahead_valid+1])
v.lookahead_valid += n
switch {
case err == os.EOF:
return Eof
case err != nil:
panic("I/O read error")
}
}
cp, _ := utf8.DecodeRune(v.lookahead[0:v.lookahead_valid])
return Make_char(cp)
}
panic("bad type")
}
// Read the next Unicode char into S.ch.
// S.ch < 0 means end-of-file.
//
func (S *Scanner) next() {
if S.rdOffset < len(S.src) {
S.offset = S.rdOffset
if S.ch == '\n' {
S.lineOffset = S.offset
S.file.AddLine(S.offset)
}
r, w := int(S.src[S.rdOffset]), 1
switch {
case r == 0:
S.error(S.offset, "illegal character NUL")
case r >= 0x80:
// not ASCII
r, w = utf8.DecodeRune(S.src[S.rdOffset:])
if r == utf8.RuneError && w == 1 {
S.error(S.offset, "illegal UTF-8 encoding")
}
}
S.rdOffset += w
S.ch = r
} else {
S.offset = len(S.src)
if S.ch == '\n' {
S.lineOffset = S.offset
S.file.AddLine(S.offset)
}
S.ch = -1 // eof
}
}
// Map returns a copy of the byte array 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(rune int) int, s []byte) []byte {
// In the worst case, the array 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
rune := int(s[i])
if rune >= utf8.RuneSelf {
rune, wid = utf8.DecodeRune(s[i:])
}
rune = mapping(rune)
if rune >= 0 {
if nbytes+utf8.RuneLen(rune) > 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], rune)
}
i += wid
}
return b[0:nbytes]
}
func (c *AutoCompleteContext) deduceDecl(file []byte, cursor int) *DeclApropos {
orig := cursor
if cursor < 0 {
return nil
}
if cursor == 0 {
return &DeclApropos{nil, ""}
}
// figure out what is just before the cursor
cursor = utf8MoveBackwards(file, cursor)
if file[cursor] == '.' {
// we're '<whatever>.'
// figure out decl, Parital is ""
return c.deduceExpr(file[:cursor], "")
} else {
letter, _ := utf8.DecodeRune(file[cursor:])
if isIdent(letter) {
// we're '<whatever>.<ident>'
// parse <ident> as Partial and figure out decl
cursor = skipIdent(file, cursor)
partial := string(file[cursor+1 : orig])
if file[cursor] == '.' {
return c.deduceExpr(file[:cursor], partial)
} else {
return &DeclApropos{nil, partial}
}
}
}
return &DeclApropos{nil, ""}
}
// Read the next Unicode char into S.ch.
// S.ch < 0 means end-of-file.
//
func (S *Scanner) next() {
if S.offset < len(S.src) {
S.pos.Offset = S.offset
S.pos.Column++
if S.ch == '\n' {
// next character starts a new line
S.pos.Line++
S.pos.Column = 1
}
r, w := int(S.src[S.offset]), 1
switch {
case r == 0:
S.error(S.pos, "illegal character NUL")
case r >= 0x80:
// not ASCII
r, w = utf8.DecodeRune(S.src[S.offset:])
if r == utf8.RuneError && w == 1 {
S.error(S.pos, "illegal UTF-8 encoding")
}
}
S.offset += w
S.ch = r
} else {
S.pos.Offset = len(S.src)
S.ch = -1 // eof
}
}
func findExpr(file []byte) []byte {
const (
LAST_NONE = iota
LAST_DOT
LAST_PAREN
LAST_IDENT
)
last := LAST_NONE
cursor := len(file)
cursor = utf8MoveBackwards(file, cursor)
loop:
for {
c := file[cursor]
letter, _ := utf8.DecodeRune(file[cursor:])
switch c {
case '.':
cursor = utf8MoveBackwards(file, cursor)
last = LAST_DOT
case ')', ']':
if last == LAST_IDENT {
break loop
}
cursor = utf8MoveBackwards(file, skipToPair(file, cursor))
last = LAST_PAREN
default:
if isIdent(letter) {
cursor = skipIdent(file, cursor)
last = LAST_IDENT
} else {
break loop
}
}
}
return file[cursor+1:]
}
// 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 {
if n == 0 {
return s // avoid allocation
}
// Compute number of replacements.
if m := Count(s, old); m == 0 {
return s // avoid allocation
} else 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]
}
// ReadRune returns the next UTF-8 encoded code point from the
// io.Reader inside r.
func (r *readRune) ReadRune() (rune int, size int, err os.Error) {
r.buf[0], err = r.readByte()
if err != nil {
return 0, 0, err
}
if r.buf[0] < utf8.RuneSelf { // fast check for common ASCII case
rune = int(r.buf[0])
return
}
var n int
for n = 1; !utf8.FullRune(r.buf[0:n]); n++ {
r.buf[n], err = r.readByte()
if err != nil {
if err == os.EOF {
err = nil
break
}
return
}
}
rune, size = utf8.DecodeRune(r.buf[0:n])
if size < n { // an error
r.unread(r.buf[size:n])
}
return
}
// next reads and returns the next Unicode character. It is designed such
// that only a minimal amount of work needs to be done in the common ASCII
// case (one test to check for both ASCII and end-of-buffer, and one test
// to check for newlines).
func (s *Scanner) next() int {
ch := int(s.srcBuf[s.srcPos])
if ch >= utf8.RuneSelf {
// uncommon case: not ASCII or not enough bytes
for s.srcPos+utf8.UTFMax > s.srcEnd && !utf8.FullRune(s.srcBuf[s.srcPos:s.srcEnd]) {
// not enough bytes: read some more, but first
// save away token text if any
if s.tokPos >= 0 {
s.tokBuf.Write(s.srcBuf[s.tokPos:s.srcPos])
s.tokPos = 0
}
// move unread bytes to beginning of buffer
copy(s.srcBuf[0:], s.srcBuf[s.srcPos:s.srcEnd])
s.srcBufOffset += s.srcPos
// read more bytes
i := s.srcEnd - s.srcPos
n, err := s.src.Read(s.srcBuf[i:bufLen])
s.srcEnd = i + n
s.srcPos = 0
s.srcBuf[s.srcEnd] = utf8.RuneSelf // sentinel
if err != nil {
if s.srcEnd == 0 {
return EOF
}
if err != os.EOF {
s.error(err.String())
break
}
}
}
// at least one byte
ch = int(s.srcBuf[s.srcPos])
if ch >= utf8.RuneSelf {
// uncommon case: not ASCII
var width int
ch, width = utf8.DecodeRune(s.srcBuf[s.srcPos:s.srcEnd])
if ch == utf8.RuneError && width == 1 {
s.error("illegal UTF-8 encoding")
}
s.srcPos += width - 1
}
}
s.srcPos++
s.column++
switch ch {
case 0:
// implementation restriction for compatibility with other tools
s.error("illegal character NUL")
case '\n':
s.line++
s.column = 0
}
return ch
}
func (i *inputBytes) step(pos int) (rune, int) {
if pos < len(i.str) {
c := i.str[pos]
if c < utf8.RuneSelf {
return rune(c), 1
}
return utf8.DecodeRune(i.str[pos:])
}
return endOfText, 0
}
func (i *inputBytes) context(pos int) syntax.EmptyOp {
r1, r2 := endOfText, endOfText
if pos > 0 && pos <= len(i.str) {
r1, _ = utf8.DecodeLastRune(i.str[:pos])
}
if pos < len(i.str) {
r2, _ = utf8.DecodeRune(i.str[pos:])
}
return syntax.EmptyOpContext(r1, r2)
}
// 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 int) 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]
}
// 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, rune int) int {
for i := 0; i < len(s); {
r, size := utf8.DecodeRune(s[i:])
if r == rune {
return i
}
i += size
}
return -1
}
// Runes returns a slice of runes (Unicode code points) equivalent to s.
func Runes(s []byte) []int {
t := make([]int, utf8.RuneCount(s))
i := 0
for len(s) > 0 {
r, l := utf8.DecodeRune(s)
t[i] = r
i++
s = s[l:]
}
return t
}
func main() {
var chars [6]int
chars[0] = 'a'
chars[1] = 'b'
chars[2] = 'c'
chars[3] = '\u65e5'
chars[4] = '\u672c'
chars[5] = '\u8a9e'
s := ""
for i := 0; i < 6; i++ {
s += string(chars[i])
}
var l = len(s)
for w, i, j := 0, 0, 0; i < l; i += w {
var r int
r, w = utf8.DecodeRuneInString(s[i:len(s)])
if w == 0 {
panic("zero width in string")
}
if r != chars[j] {
panic("wrong value from string")
}
j++
}
// encoded as bytes: 'a' 'b' 'c' e6 97 a5 e6 9c ac e8 aa 9e
const L = 12
if L != l {
panic("wrong length constructing array")
}
a := make([]byte, L)
a[0] = 'a'
a[1] = 'b'
a[2] = 'c'
a[3] = 0xe6
a[4] = 0x97
a[5] = 0xa5
a[6] = 0xe6
a[7] = 0x9c
a[8] = 0xac
a[9] = 0xe8
a[10] = 0xaa
a[11] = 0x9e
for w, i, j := 0, 0, 0; i < L; i += w {
var r int
r, w = utf8.DecodeRune(a[i:L])
if w == 0 {
panic("zero width in bytes")
}
if r != chars[j] {
panic("wrong value from bytes")
}
j++
}
}
func (S *Lexer) getChar() (ch int, w int) {
ch, w = int(S.input[S.readOffset]), 1
switch {
case ch == 0:
S.error("illegal 0")
case ch >= 0x80:
ch, w = utf8.DecodeRune(S.input[S.readOffset:])
if ch == utf8.RuneError && w == 1 {
S.error("illegal utf")
}
}
return
}
func skipIdent(file []byte, cursor int) int {
for {
letter, _ := utf8.DecodeRune(file[cursor:])
if !isIdent(letter) {
return cursor
}
cursor = utf8MoveBackwards(file, cursor)
if cursor <= 0 {
return 0
}
}
return 0
}
/*
Capitalizes the first character of the value.
Example:
{value|capfirst}
If value is "neste", the output will be "Neste".
*/
func CapFirstFormatter(w io.Writer, formatter string, data ...interface{}) {
b := getBytes(data...)
if len(b) > 0 {
rune, size := utf8.DecodeRune(b)
rune = unicode.ToUpper(rune)
capSize := utf8.RuneLen(rune)
capb := make([]byte, capSize)
utf8.EncodeRune(capb, rune)
w.Write(capb)
w.Write(b[size:])
}
}
// Parses the next rune and checks to see if its in a given range
func pRange(ranges []unicode.Range, result *string, src []byte, i *int) bool {
rune, size := utf8.DecodeRune(src[i : i+utf8.UTF8Max])
if unicode.Is(ranges, rune) {
buf := make([]byte, size)
utf8.EncodeRune(rune, buf)
*result = string(buf) // return resulting rune
*i += size // Update index
//src = src[size:len(src)]; // Update slice
return true
}
// No match
return false
}
// Find matches in slice b if b is non-nil, otherwise find matches in string s.
func (re *Regexp) allMatches(s string, b []byte, n int, deliver func([]int)) {
var end int
if b == nil {
end = len(s)
} else {
end = len(b)
}
for pos, i, prevMatchEnd := 0, 0, -1; i < n && pos <= end; {
var in input
if b == nil {
in = newInputString(s)
} else {
in = newInputBytes(b)
}
matches := re.doExecute(in, pos, re.prog.NumCap)
if len(matches) == 0 {
break
}
accept := true
if matches[1] == pos {
// We've found an empty match.
if matches[0] == prevMatchEnd {
// We don't allow an empty match right
// after a previous match, so ignore it.
accept = false
}
var width int
// TODO: use step()
if b == nil {
_, width = utf8.DecodeRuneInString(s[pos:end])
} else {
_, width = utf8.DecodeRune(b[pos:end])
}
if width > 0 {
pos += width
} else {
pos = end + 1
}
} else {
pos = matches[1]
}
prevMatchEnd = matches[1]
if accept {
deliver(re.pad(matches))
i++
}
}
}
// Specialized function for TeX-style hyphenation patterns. Accepts strings of the form '.hy2p'.
// The value it stores is of type vector.IntVector
func (p *Trie) AddPatternString(s string) {
v := new(vector.IntVector)
// precompute the Unicode rune for the character '0'
rune0, _ := utf8.DecodeRune([]byte{'0'})
strLen := len(s)
// Using the range keyword will give us each Unicode rune.
for pos, rune := range s {
if unicode.IsDigit(rune) {
if pos == 0 {
// This is a prefix number
v.Push(rune - rune0)
}
// this is a number referring to the previous character, and has
// already been handled
continue
}
if pos < strLen-1 {
// look ahead to see if it's followed by a number
next := int(s[pos+1])
if unicode.IsDigit(next) {
// next char is the hyphenation value for this char
v.Push(next - rune0)
} else {
// hyphenation for this char is an implied zero
v.Push(0)
}
} else {
// last character gets an implied zero
v.Push(0)
}
}
pure := strings.Map(func(rune int) int {
if unicode.IsDigit(rune) {
return -1
}
return rune
},
s)
leaf := p.addRunes(strings.NewReader(pure))
if leaf == nil {
return
}
leaf.value = v
}
// ReadRune reads a single UTF-8 encoded Unicode character and returns the
// rune and its size in bytes.
func (b *Reader) ReadRune() (rune int, size int, err os.Error) {
for b.r+utf8.UTFMax > b.w && !utf8.FullRune(b.buf[b.r:b.w]) && b.err == nil {
b.fill()
}
if b.r == b.w {
return 0, 0, b.err
}
rune, size = int(b.buf[b.r]), 1
if rune >= 0x80 {
rune, size = utf8.DecodeRune(b.buf[b.r:b.w])
}
b.r += size
b.lastbyte = int(b.buf[b.r-1])
return rune, size, nil
}
// 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 int) bool, truth bool) int {
start := 0
for start < len(s) {
wid := 1
rune := int(s[start])
if rune >= utf8.RuneSelf {
rune, wid = utf8.DecodeRune(s[start:])
}
if f(rune) == truth {
return start
}
start += wid
}
return -1
}
// ReadRune reads and returns the next UTF-8-encoded
// Unicode code point from the buffer.
// If no bytes are available, the error returned is os.EOF.
// If the bytes are an erroneous UTF-8 encoding, it
// consumes one byte and returns U+FFFD, 1.
func (b *Buffer) ReadRune() (r int, size int, err os.Error) {
if b.off >= len(b.buf) {
// Buffer is empty, reset to recover space.
b.Truncate(0)
return 0, 0, os.EOF
}
c := b.buf[b.off]
if c < utf8.RuneSelf {
b.off++
return int(c), 1, nil
}
r, n := utf8.DecodeRune(b.buf[b.off:])
b.off += n
return r, n, nil
}