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-rw-r--r--src/text/scanner/scanner.go793
1 files changed, 793 insertions, 0 deletions
diff --git a/src/text/scanner/scanner.go b/src/text/scanner/scanner.go
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+// 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 scanner provides a scanner and tokenizer for UTF-8-encoded text.
+// It takes an io.Reader providing the source, which then can be tokenized
+// through repeated calls to the Scan function. For compatibility with
+// existing tools, the NUL character is not allowed. If the first character
+// in the source is a UTF-8 encoded byte order mark (BOM), it is discarded.
+//
+// By default, a Scanner skips white space and Go comments and recognizes all
+// literals as defined by the Go language specification. It may be
+// customized to recognize only a subset of those literals and to recognize
+// different identifier and white space characters.
+package scanner
+
+import (
+ "bytes"
+ "fmt"
+ "io"
+ "os"
+ "unicode"
+ "unicode/utf8"
+)
+
+// A source position is represented by a Position value.
+// A position is valid if Line > 0.
+type Position struct {
+ Filename string // filename, if any
+ Offset int // byte offset, starting at 0
+ Line int // line number, starting at 1
+ Column int // column number, starting at 1 (character count per line)
+}
+
+// IsValid reports whether the position is valid.
+func (pos *Position) IsValid() bool { return pos.Line > 0 }
+
+func (pos Position) String() string {
+ s := pos.Filename
+ if s == "" {
+ s = "<input>"
+ }
+ if pos.IsValid() {
+ s += fmt.Sprintf(":%d:%d", pos.Line, pos.Column)
+ }
+ return s
+}
+
+// Predefined mode bits to control recognition of tokens. For instance,
+// to configure a Scanner such that it only recognizes (Go) identifiers,
+// integers, and skips comments, set the Scanner's Mode field to:
+//
+// ScanIdents | ScanInts | SkipComments
+//
+// With the exceptions of comments, which are skipped if SkipComments is
+// set, unrecognized tokens are not ignored. Instead, the scanner simply
+// returns the respective individual characters (or possibly sub-tokens).
+// For instance, if the mode is ScanIdents (not ScanStrings), the string
+// "foo" is scanned as the token sequence '"' Ident '"'.
+//
+// Use GoTokens to configure the Scanner such that it accepts all Go
+// literal tokens including Go identifiers. Comments will be skipped.
+//
+const (
+ ScanIdents = 1 << -Ident
+ ScanInts = 1 << -Int
+ ScanFloats = 1 << -Float // includes Ints and hexadecimal floats
+ ScanChars = 1 << -Char
+ ScanStrings = 1 << -String
+ ScanRawStrings = 1 << -RawString
+ ScanComments = 1 << -Comment
+ SkipComments = 1 << -skipComment // if set with ScanComments, comments become white space
+ GoTokens = ScanIdents | ScanFloats | ScanChars | ScanStrings | ScanRawStrings | ScanComments | SkipComments
+)
+
+// The result of Scan is one of these tokens or a Unicode character.
+const (
+ EOF = -(iota + 1)
+ Ident
+ Int
+ Float
+ Char
+ String
+ RawString
+ Comment
+
+ // internal use only
+ skipComment
+)
+
+var tokenString = map[rune]string{
+ EOF: "EOF",
+ Ident: "Ident",
+ Int: "Int",
+ Float: "Float",
+ Char: "Char",
+ String: "String",
+ RawString: "RawString",
+ Comment: "Comment",
+}
+
+// TokenString returns a printable string for a token or Unicode character.
+func TokenString(tok rune) string {
+ if s, found := tokenString[tok]; found {
+ return s
+ }
+ return fmt.Sprintf("%q", string(tok))
+}
+
+// GoWhitespace is the default value for the Scanner's Whitespace field.
+// Its value selects Go's white space characters.
+const GoWhitespace = 1<<'\t' | 1<<'\n' | 1<<'\r' | 1<<' '
+
+const bufLen = 1024 // at least utf8.UTFMax
+
+// A Scanner implements reading of Unicode characters and tokens from an io.Reader.
+type Scanner struct {
+ // Input
+ src io.Reader
+
+ // Source buffer
+ srcBuf [bufLen + 1]byte // +1 for sentinel for common case of s.next()
+ srcPos int // reading position (srcBuf index)
+ srcEnd int // source end (srcBuf index)
+
+ // Source position
+ srcBufOffset int // byte offset of srcBuf[0] in source
+ line int // line count
+ column int // character count
+ lastLineLen int // length of last line in characters (for correct column reporting)
+ lastCharLen int // length of last character in bytes
+
+ // Token text buffer
+ // Typically, token text is stored completely in srcBuf, but in general
+ // the token text's head may be buffered in tokBuf while the token text's
+ // tail is stored in srcBuf.
+ tokBuf bytes.Buffer // token text head that is not in srcBuf anymore
+ tokPos int // token text tail position (srcBuf index); valid if >= 0
+ tokEnd int // token text tail end (srcBuf index)
+
+ // One character look-ahead
+ ch rune // character before current srcPos
+
+ // Error is called for each error encountered. If no Error
+ // function is set, the error is reported to os.Stderr.
+ Error func(s *Scanner, msg string)
+
+ // ErrorCount is incremented by one for each error encountered.
+ ErrorCount int
+
+ // The Mode field controls which tokens are recognized. For instance,
+ // to recognize Ints, set the ScanInts bit in Mode. The field may be
+ // changed at any time.
+ Mode uint
+
+ // The Whitespace field controls which characters are recognized
+ // as white space. To recognize a character ch <= ' ' as white space,
+ // set the ch'th bit in Whitespace (the Scanner's behavior is undefined
+ // for values ch > ' '). The field may be changed at any time.
+ Whitespace uint64
+
+ // IsIdentRune is a predicate controlling the characters accepted
+ // as the ith rune in an identifier. The set of valid characters
+ // must not intersect with the set of white space characters.
+ // If no IsIdentRune function is set, regular Go identifiers are
+ // accepted instead. The field may be changed at any time.
+ IsIdentRune func(ch rune, i int) bool
+
+ // Start position of most recently scanned token; set by Scan.
+ // Calling Init or Next invalidates the position (Line == 0).
+ // The Filename field is always left untouched by the Scanner.
+ // If an error is reported (via Error) and Position is invalid,
+ // the scanner is not inside a token. Call Pos to obtain an error
+ // position in that case, or to obtain the position immediately
+ // after the most recently scanned token.
+ Position
+}
+
+// Init initializes a Scanner with a new source and returns s.
+// Error is set to nil, ErrorCount is set to 0, Mode is set to GoTokens,
+// and Whitespace is set to GoWhitespace.
+func (s *Scanner) Init(src io.Reader) *Scanner {
+ s.src = src
+
+ // initialize source buffer
+ // (the first call to next() will fill it by calling src.Read)
+ s.srcBuf[0] = utf8.RuneSelf // sentinel
+ s.srcPos = 0
+ s.srcEnd = 0
+
+ // initialize source position
+ s.srcBufOffset = 0
+ s.line = 1
+ s.column = 0
+ s.lastLineLen = 0
+ s.lastCharLen = 0
+
+ // initialize token text buffer
+ // (required for first call to next()).
+ s.tokPos = -1
+
+ // initialize one character look-ahead
+ s.ch = -2 // no char read yet, not EOF
+
+ // initialize public fields
+ s.Error = nil
+ s.ErrorCount = 0
+ s.Mode = GoTokens
+ s.Whitespace = GoWhitespace
+ s.Line = 0 // invalidate token position
+
+ return s
+}
+
+// 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() rune {
+ ch, width := rune(s.srcBuf[s.srcPos]), 1
+
+ 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
+ // s.tokEnd is set by Scan()
+ }
+ // move unread bytes to beginning of buffer
+ copy(s.srcBuf[0:], s.srcBuf[s.srcPos:s.srcEnd])
+ s.srcBufOffset += s.srcPos
+ // read more bytes
+ // (an io.Reader must return io.EOF when it reaches
+ // the end of what it is reading - simply returning
+ // n == 0 will make this loop retry forever; but the
+ // error is in the reader implementation in that case)
+ i := s.srcEnd - s.srcPos
+ n, err := s.src.Read(s.srcBuf[i:bufLen])
+ s.srcPos = 0
+ s.srcEnd = i + n
+ s.srcBuf[s.srcEnd] = utf8.RuneSelf // sentinel
+ if err != nil {
+ if err != io.EOF {
+ s.error(err.Error())
+ }
+ if s.srcEnd == 0 {
+ if s.lastCharLen > 0 {
+ // previous character was not EOF
+ s.column++
+ }
+ s.lastCharLen = 0
+ return EOF
+ }
+ // If err == EOF, we won't be getting more
+ // bytes; break to avoid infinite loop. If
+ // err is something else, we don't know if
+ // we can get more bytes; thus also break.
+ break
+ }
+ }
+ // at least one byte
+ ch = rune(s.srcBuf[s.srcPos])
+ if ch >= utf8.RuneSelf {
+ // uncommon case: not ASCII
+ ch, width = utf8.DecodeRune(s.srcBuf[s.srcPos:s.srcEnd])
+ if ch == utf8.RuneError && width == 1 {
+ // advance for correct error position
+ s.srcPos += width
+ s.lastCharLen = width
+ s.column++
+ s.error("invalid UTF-8 encoding")
+ return ch
+ }
+ }
+ }
+
+ // advance
+ s.srcPos += width
+ s.lastCharLen = width
+ s.column++
+
+ // special situations
+ switch ch {
+ case 0:
+ // for compatibility with other tools
+ s.error("invalid character NUL")
+ case '\n':
+ s.line++
+ s.lastLineLen = s.column
+ s.column = 0
+ }
+
+ return ch
+}
+
+// Next reads and returns the next Unicode character.
+// It returns EOF at the end of the source. It reports
+// a read error by calling s.Error, if not nil; otherwise
+// it prints an error message to os.Stderr. Next does not
+// update the Scanner's Position field; use Pos() to
+// get the current position.
+func (s *Scanner) Next() rune {
+ s.tokPos = -1 // don't collect token text
+ s.Line = 0 // invalidate token position
+ ch := s.Peek()
+ if ch != EOF {
+ s.ch = s.next()
+ }
+ return ch
+}
+
+// Peek returns the next Unicode character in the source without advancing
+// the scanner. It returns EOF if the scanner's position is at the last
+// character of the source.
+func (s *Scanner) Peek() rune {
+ if s.ch == -2 {
+ // this code is only run for the very first character
+ s.ch = s.next()
+ if s.ch == '\uFEFF' {
+ s.ch = s.next() // ignore BOM
+ }
+ }
+ return s.ch
+}
+
+func (s *Scanner) error(msg string) {
+ s.tokEnd = s.srcPos - s.lastCharLen // make sure token text is terminated
+ s.ErrorCount++
+ if s.Error != nil {
+ s.Error(s, msg)
+ return
+ }
+ pos := s.Position
+ if !pos.IsValid() {
+ pos = s.Pos()
+ }
+ fmt.Fprintf(os.Stderr, "%s: %s\n", pos, msg)
+}
+
+func (s *Scanner) errorf(format string, args ...interface{}) {
+ s.error(fmt.Sprintf(format, args...))
+}
+
+func (s *Scanner) isIdentRune(ch rune, i int) bool {
+ if s.IsIdentRune != nil {
+ return s.IsIdentRune(ch, i)
+ }
+ return ch == '_' || unicode.IsLetter(ch) || unicode.IsDigit(ch) && i > 0
+}
+
+func (s *Scanner) scanIdentifier() rune {
+ // we know the zero'th rune is OK; start scanning at the next one
+ ch := s.next()
+ for i := 1; s.isIdentRune(ch, i); i++ {
+ ch = s.next()
+ }
+ return ch
+}
+
+func lower(ch rune) rune { return ('a' - 'A') | ch } // returns lower-case ch iff ch is ASCII letter
+func isDecimal(ch rune) bool { return '0' <= ch && ch <= '9' }
+func isHex(ch rune) bool { return '0' <= ch && ch <= '9' || 'a' <= lower(ch) && lower(ch) <= 'f' }
+
+// digits accepts the sequence { digit | '_' } starting with ch0.
+// If base <= 10, digits accepts any decimal digit but records
+// the first invalid digit >= base in *invalid if *invalid == 0.
+// digits returns the first rune that is not part of the sequence
+// anymore, and a bitset describing whether the sequence contained
+// digits (bit 0 is set), or separators '_' (bit 1 is set).
+func (s *Scanner) digits(ch0 rune, base int, invalid *rune) (ch rune, digsep int) {
+ ch = ch0
+ if base <= 10 {
+ max := rune('0' + base)
+ for isDecimal(ch) || ch == '_' {
+ ds := 1
+ if ch == '_' {
+ ds = 2
+ } else if ch >= max && *invalid == 0 {
+ *invalid = ch
+ }
+ digsep |= ds
+ ch = s.next()
+ }
+ } else {
+ for isHex(ch) || ch == '_' {
+ ds := 1
+ if ch == '_' {
+ ds = 2
+ }
+ digsep |= ds
+ ch = s.next()
+ }
+ }
+ return
+}
+
+func (s *Scanner) scanNumber(ch rune, seenDot bool) (rune, rune) {
+ base := 10 // number base
+ prefix := rune(0) // one of 0 (decimal), '0' (0-octal), 'x', 'o', or 'b'
+ digsep := 0 // bit 0: digit present, bit 1: '_' present
+ invalid := rune(0) // invalid digit in literal, or 0
+
+ // integer part
+ var tok rune
+ var ds int
+ if !seenDot {
+ tok = Int
+ if ch == '0' {
+ ch = s.next()
+ switch lower(ch) {
+ case 'x':
+ ch = s.next()
+ base, prefix = 16, 'x'
+ case 'o':
+ ch = s.next()
+ base, prefix = 8, 'o'
+ case 'b':
+ ch = s.next()
+ base, prefix = 2, 'b'
+ default:
+ base, prefix = 8, '0'
+ digsep = 1 // leading 0
+ }
+ }
+ ch, ds = s.digits(ch, base, &invalid)
+ digsep |= ds
+ if ch == '.' && s.Mode&ScanFloats != 0 {
+ ch = s.next()
+ seenDot = true
+ }
+ }
+
+ // fractional part
+ if seenDot {
+ tok = Float
+ if prefix == 'o' || prefix == 'b' {
+ s.error("invalid radix point in " + litname(prefix))
+ }
+ ch, ds = s.digits(ch, base, &invalid)
+ digsep |= ds
+ }
+
+ if digsep&1 == 0 {
+ s.error(litname(prefix) + " has no digits")
+ }
+
+ // exponent
+ if e := lower(ch); (e == 'e' || e == 'p') && s.Mode&ScanFloats != 0 {
+ switch {
+ case e == 'e' && prefix != 0 && prefix != '0':
+ s.errorf("%q exponent requires decimal mantissa", ch)
+ case e == 'p' && prefix != 'x':
+ s.errorf("%q exponent requires hexadecimal mantissa", ch)
+ }
+ ch = s.next()
+ tok = Float
+ if ch == '+' || ch == '-' {
+ ch = s.next()
+ }
+ ch, ds = s.digits(ch, 10, nil)
+ digsep |= ds
+ if ds&1 == 0 {
+ s.error("exponent has no digits")
+ }
+ } else if prefix == 'x' && tok == Float {
+ s.error("hexadecimal mantissa requires a 'p' exponent")
+ }
+
+ if tok == Int && invalid != 0 {
+ s.errorf("invalid digit %q in %s", invalid, litname(prefix))
+ }
+
+ if digsep&2 != 0 {
+ s.tokEnd = s.srcPos - s.lastCharLen // make sure token text is terminated
+ if i := invalidSep(s.TokenText()); i >= 0 {
+ s.error("'_' must separate successive digits")
+ }
+ }
+
+ return tok, ch
+}
+
+func litname(prefix rune) string {
+ switch prefix {
+ default:
+ return "decimal literal"
+ case 'x':
+ return "hexadecimal literal"
+ case 'o', '0':
+ return "octal literal"
+ case 'b':
+ return "binary literal"
+ }
+}
+
+// invalidSep returns the index of the first invalid separator in x, or -1.
+func invalidSep(x string) int {
+ x1 := ' ' // prefix char, we only care if it's 'x'
+ d := '.' // digit, one of '_', '0' (a digit), or '.' (anything else)
+ i := 0
+
+ // a prefix counts as a digit
+ if len(x) >= 2 && x[0] == '0' {
+ x1 = lower(rune(x[1]))
+ if x1 == 'x' || x1 == 'o' || x1 == 'b' {
+ d = '0'
+ i = 2
+ }
+ }
+
+ // mantissa and exponent
+ for ; i < len(x); i++ {
+ p := d // previous digit
+ d = rune(x[i])
+ switch {
+ case d == '_':
+ if p != '0' {
+ return i
+ }
+ case isDecimal(d) || x1 == 'x' && isHex(d):
+ d = '0'
+ default:
+ if p == '_' {
+ return i - 1
+ }
+ d = '.'
+ }
+ }
+ if d == '_' {
+ return len(x) - 1
+ }
+
+ return -1
+}
+
+func digitVal(ch rune) int {
+ switch {
+ case '0' <= ch && ch <= '9':
+ return int(ch - '0')
+ case 'a' <= lower(ch) && lower(ch) <= 'f':
+ return int(lower(ch) - 'a' + 10)
+ }
+ return 16 // larger than any legal digit val
+}
+
+func (s *Scanner) scanDigits(ch rune, base, n int) rune {
+ for n > 0 && digitVal(ch) < base {
+ ch = s.next()
+ n--
+ }
+ if n > 0 {
+ s.error("invalid char escape")
+ }
+ return ch
+}
+
+func (s *Scanner) scanEscape(quote rune) rune {
+ ch := s.next() // read character after '/'
+ switch ch {
+ case 'a', 'b', 'f', 'n', 'r', 't', 'v', '\\', quote:
+ // nothing to do
+ ch = s.next()
+ case '0', '1', '2', '3', '4', '5', '6', '7':
+ ch = s.scanDigits(ch, 8, 3)
+ case 'x':
+ ch = s.scanDigits(s.next(), 16, 2)
+ case 'u':
+ ch = s.scanDigits(s.next(), 16, 4)
+ case 'U':
+ ch = s.scanDigits(s.next(), 16, 8)
+ default:
+ s.error("invalid char escape")
+ }
+ return ch
+}
+
+func (s *Scanner) scanString(quote rune) (n int) {
+ ch := s.next() // read character after quote
+ for ch != quote {
+ if ch == '\n' || ch < 0 {
+ s.error("literal not terminated")
+ return
+ }
+ if ch == '\\' {
+ ch = s.scanEscape(quote)
+ } else {
+ ch = s.next()
+ }
+ n++
+ }
+ return
+}
+
+func (s *Scanner) scanRawString() {
+ ch := s.next() // read character after '`'
+ for ch != '`' {
+ if ch < 0 {
+ s.error("literal not terminated")
+ return
+ }
+ ch = s.next()
+ }
+}
+
+func (s *Scanner) scanChar() {
+ if s.scanString('\'') != 1 {
+ s.error("invalid char literal")
+ }
+}
+
+func (s *Scanner) scanComment(ch rune) rune {
+ // ch == '/' || ch == '*'
+ if ch == '/' {
+ // line comment
+ ch = s.next() // read character after "//"
+ for ch != '\n' && ch >= 0 {
+ ch = s.next()
+ }
+ return ch
+ }
+
+ // general comment
+ ch = s.next() // read character after "/*"
+ for {
+ if ch < 0 {
+ s.error("comment not terminated")
+ break
+ }
+ ch0 := ch
+ ch = s.next()
+ if ch0 == '*' && ch == '/' {
+ ch = s.next()
+ break
+ }
+ }
+ return ch
+}
+
+// Scan reads the next token or Unicode character from source and returns it.
+// It only recognizes tokens t for which the respective Mode bit (1<<-t) is set.
+// It returns EOF at the end of the source. It reports scanner errors (read and
+// token errors) by calling s.Error, if not nil; otherwise it prints an error
+// message to os.Stderr.
+func (s *Scanner) Scan() rune {
+ ch := s.Peek()
+
+ // reset token text position
+ s.tokPos = -1
+ s.Line = 0
+
+redo:
+ // skip white space
+ for s.Whitespace&(1<<uint(ch)) != 0 {
+ ch = s.next()
+ }
+
+ // start collecting token text
+ s.tokBuf.Reset()
+ s.tokPos = s.srcPos - s.lastCharLen
+
+ // set token position
+ // (this is a slightly optimized version of the code in Pos())
+ s.Offset = s.srcBufOffset + s.tokPos
+ if s.column > 0 {
+ // common case: last character was not a '\n'
+ s.Line = s.line
+ s.Column = s.column
+ } else {
+ // last character was a '\n'
+ // (we cannot be at the beginning of the source
+ // since we have called next() at least once)
+ s.Line = s.line - 1
+ s.Column = s.lastLineLen
+ }
+
+ // determine token value
+ tok := ch
+ switch {
+ case s.isIdentRune(ch, 0):
+ if s.Mode&ScanIdents != 0 {
+ tok = Ident
+ ch = s.scanIdentifier()
+ } else {
+ ch = s.next()
+ }
+ case isDecimal(ch):
+ if s.Mode&(ScanInts|ScanFloats) != 0 {
+ tok, ch = s.scanNumber(ch, false)
+ } else {
+ ch = s.next()
+ }
+ default:
+ switch ch {
+ case EOF:
+ break
+ case '"':
+ if s.Mode&ScanStrings != 0 {
+ s.scanString('"')
+ tok = String
+ }
+ ch = s.next()
+ case '\'':
+ if s.Mode&ScanChars != 0 {
+ s.scanChar()
+ tok = Char
+ }
+ ch = s.next()
+ case '.':
+ ch = s.next()
+ if isDecimal(ch) && s.Mode&ScanFloats != 0 {
+ tok, ch = s.scanNumber(ch, true)
+ }
+ case '/':
+ ch = s.next()
+ if (ch == '/' || ch == '*') && s.Mode&ScanComments != 0 {
+ if s.Mode&SkipComments != 0 {
+ s.tokPos = -1 // don't collect token text
+ ch = s.scanComment(ch)
+ goto redo
+ }
+ ch = s.scanComment(ch)
+ tok = Comment
+ }
+ case '`':
+ if s.Mode&ScanRawStrings != 0 {
+ s.scanRawString()
+ tok = RawString
+ }
+ ch = s.next()
+ default:
+ ch = s.next()
+ }
+ }
+
+ // end of token text
+ s.tokEnd = s.srcPos - s.lastCharLen
+
+ s.ch = ch
+ return tok
+}
+
+// Pos returns the position of the character immediately after
+// the character or token returned by the last call to Next or Scan.
+// Use the Scanner's Position field for the start position of the most
+// recently scanned token.
+func (s *Scanner) Pos() (pos Position) {
+ pos.Filename = s.Filename
+ pos.Offset = s.srcBufOffset + s.srcPos - s.lastCharLen
+ switch {
+ case s.column > 0:
+ // common case: last character was not a '\n'
+ pos.Line = s.line
+ pos.Column = s.column
+ case s.lastLineLen > 0:
+ // last character was a '\n'
+ pos.Line = s.line - 1
+ pos.Column = s.lastLineLen
+ default:
+ // at the beginning of the source
+ pos.Line = 1
+ pos.Column = 1
+ }
+ return
+}
+
+// TokenText returns the string corresponding to the most recently scanned token.
+// Valid after calling Scan and in calls of Scanner.Error.
+func (s *Scanner) TokenText() string {
+ if s.tokPos < 0 {
+ // no token text
+ return ""
+ }
+
+ if s.tokEnd < s.tokPos {
+ // if EOF was reached, s.tokEnd is set to -1 (s.srcPos == 0)
+ s.tokEnd = s.tokPos
+ }
+ // s.tokEnd >= s.tokPos
+
+ if s.tokBuf.Len() == 0 {
+ // common case: the entire token text is still in srcBuf
+ return string(s.srcBuf[s.tokPos:s.tokEnd])
+ }
+
+ // part of the token text was saved in tokBuf: save the rest in
+ // tokBuf as well and return its content
+ s.tokBuf.Write(s.srcBuf[s.tokPos:s.tokEnd])
+ s.tokPos = s.tokEnd // ensure idempotency of TokenText() call
+ return s.tokBuf.String()
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-15 15:41:54 +0000