// Copyright 2011 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// Features shared by parsing and pre-parsing scanners.
#include "../include/v8stdint.h"
#include "scanner-base.h"
#include "char-predicates-inl.h"
namespace v8 {
namespace internal {
// ----------------------------------------------------------------------------
// Scanner
Scanner::Scanner(UnicodeCache* unicode_cache)
: unicode_cache_(unicode_cache),
octal_pos_(kNoOctalLocation) { }
uc32 Scanner::ScanHexEscape(uc32 c, int length) {
ASSERT(length <= 4); // prevent overflow
uc32 digits[4];
uc32 x = 0;
for (int i = 0; i < length; i++) {
digits[i] = c0_;
int d = HexValue(c0_);
if (d < 0) {
// According to ECMA-262, 3rd, 7.8.4, page 18, these hex escapes
// should be illegal, but other JS VMs just return the
// non-escaped version of the original character.
// Push back digits read, except the last one (in c0_).
for (int j = i-1; j >= 0; j--) {
PushBack(digits[j]);
}
// Notice: No handling of error - treat it as "\u"->"u".
return c;
}
x = x * 16 + d;
Advance();
}
return x;
}
// Octal escapes of the forms '\0xx' and '\xxx' are not a part of
// ECMA-262. Other JS VMs support them.
uc32 Scanner::ScanOctalEscape(uc32 c, int length) {
uc32 x = c - '0';
int i = 0;
for (; i < length; i++) {
int d = c0_ - '0';
if (d < 0 || d > 7) break;
int nx = x * 8 + d;
if (nx >= 256) break;
x = nx;
Advance();
}
// Anything excelt '\0' is an octal escape sequence, illegal in strict mode.
// Remember the position of octal escape sequences so that better error
// can be reported later (in strict mode).
if (c != '0' || i > 0) {
octal_pos_ = source_pos() - i - 1; // Already advanced
}
return x;
}
// ----------------------------------------------------------------------------
// JavaScriptScanner
JavaScriptScanner::JavaScriptScanner(UnicodeCache* scanner_contants)
: Scanner(scanner_contants) { }
Token::Value JavaScriptScanner::Next() {
current_ = next_;
has_line_terminator_before_next_ = false;
Scan();
return current_.token;
}
static inline bool IsByteOrderMark(uc32 c) {
// The Unicode value U+FFFE is guaranteed never to be assigned as a
// Unicode character; this implies that in a Unicode context the
// 0xFF, 0xFE byte pattern can only be interpreted as the U+FEFF
// character expressed in little-endian byte order (since it could
// not be a U+FFFE character expressed in big-endian byte
// order). Nevertheless, we check for it to be compatible with
// Spidermonkey.
return c == 0xFEFF || c == 0xFFFE;
}
bool JavaScriptScanner::SkipWhiteSpace() {
int start_position = source_pos();
while (true) {
// We treat byte-order marks (BOMs) as whitespace for better
// compatibility with Spidermonkey and other JavaScript engines.
while (unicode_cache_->IsWhiteSpace(c0_) || IsByteOrderMark(c0_)) {
// IsWhiteSpace() includes line terminators!
if (unicode_cache_->IsLineTerminator(c0_)) {
// Ignore line terminators, but remember them. This is necessary
// for automatic semicolon insertion.
has_line_terminator_before_next_ = true;
}
Advance();
}
// If there is an HTML comment end '-->' at the beginning of a
// line (with only whitespace in front of it), we treat the rest
// of the line as a comment. This is in line with the way
// SpiderMonkey handles it.
if (c0_ == '-' && has_line_terminator_before_next_) {
Advance();
if (c0_ == '-') {
Advance();
if (c0_ == '>') {
// Treat the rest of the line as a comment.
SkipSingleLineComment();
// Continue skipping white space after the comment.
continue;
}
PushBack('-'); // undo Advance()
}
PushBack('-'); // undo Advance()
}
// Return whether or not we skipped any characters.
return source_pos() != start_position;
}
}
Token::Value JavaScriptScanner::SkipSingleLineComment() {
Advance();
// The line terminator at the end of the line is not considered
// to be part of the single-line comment; it is recognized
// separately by the lexical grammar and becomes part of the
// stream of input elements for the syntactic grammar (see
// ECMA-262, section 7.4, page 12).
while (c0_ >= 0 && !unicode_cache_->IsLineTerminator(c0_)) {
Advance();
}
return Token::WHITESPACE;
}
Token::Value JavaScriptScanner::SkipMultiLineComment() {
ASSERT(c0_ == '*');
Advance();
while (c0_ >= 0) {
char ch = c0_;
Advance();
// If we have reached the end of the multi-line comment, we
// consume the '/' and insert a whitespace. This way all
// multi-line comments are treated as whitespace - even the ones
// containing line terminators. This contradicts ECMA-262, section
// 7.4, page 12, that says that multi-line comments containing
// line terminators should be treated as a line terminator, but it
// matches the behaviour of SpiderMonkey and KJS.
if (ch == '*' && c0_ == '/') {
c0_ = ' ';
return Token::WHITESPACE;
}
}
// Unterminated multi-line comment.
return Token::ILLEGAL;
}
Token::Value JavaScriptScanner::ScanHtmlComment() {
// Check for <!-- comments.
ASSERT(c0_ == '!');
Advance();
if (c0_ == '-') {
Advance();
if (c0_ == '-') return SkipSingleLineComment();
PushBack('-'); // undo Advance()
}
PushBack('!'); // undo Advance()
ASSERT(c0_ == '!');
return Token::LT;
}
void JavaScriptScanner::Scan() {
next_.literal_chars = NULL;
Token::Value token;
do {
// Remember the position of the next token
next_.location.beg_pos = source_pos();
switch (c0_) {
case ' ':
case '\t':
Advance();
token = Token::WHITESPACE;
break;
case '\n':
Advance();
has_line_terminator_before_next_ = true;
token = Token::WHITESPACE;
break;
case '"': case '\'':
token = ScanString();
break;
case '<':
// < <= << <<= <!--
Advance();
if (c0_ == '=') {
token = Select(Token::LTE);
} else if (c0_ == '<') {
token = Select('=', Token::ASSIGN_SHL, Token::SHL);
} else if (c0_ == '!') {
token = ScanHtmlComment();
} else {
token = Token::LT;
}
break;
case '>':
// > >= >> >>= >>> >>>=
Advance();
if (c0_ == '=') {
token = Select(Token::GTE);
} else if (c0_ == '>') {
// >> >>= >>> >>>=
Advance();
if (c0_ == '=') {
token = Select(Token::ASSIGN_SAR);
} else if (c0_ == '>') {
token = Select('=', Token::ASSIGN_SHR, Token::SHR);
} else {
token = Token::SAR;
}
} else {
token = Token::GT;
}
break;
case '=':
// = == ===
Advance();
if (c0_ == '=') {
token = Select('=', Token::EQ_STRICT, Token::EQ);
} else {
token = Token::ASSIGN;
}
break;
case '!':
// ! != !==
Advance();
if (c0_ == '=') {
token = Select('=', Token::NE_STRICT, Token::NE);
} else {
token = Token::NOT;
}
break;
case '+':
// + ++ +=
Advance();
if (c0_ == '+') {
token = Select(Token::INC);
} else if (c0_ == '=') {
token = Select(Token::ASSIGN_ADD);
} else {
token = Token::ADD;
}
break;
case '-':
// - -- --> -=
Advance();
if (c0_ == '-') {
Advance();
if (c0_ == '>' && has_line_terminator_before_next_) {
// For compatibility with SpiderMonkey, we skip lines that
// start with an HTML comment end '-->'.
token = SkipSingleLineComment();
} else {
token = Token::DEC;
}
} else if (c0_ == '=') {
token = Select(Token::ASSIGN_SUB);
} else {
token = Token::SUB;
}
break;
case '*':
// * *=
token = Select('=', Token::ASSIGN_MUL, Token::MUL);
break;
case '%':
// % %=
token = Select('=', Token::ASSIGN_MOD, Token::MOD);
break;
case '/':
// / // /* /=
Advance();
if (c0_ == '/') {
token = SkipSingleLineComment();
} else if (c0_ == '*') {
token = SkipMultiLineComment();
} else if (c0_ == '=') {
token = Select(Token::ASSIGN_DIV);
} else {
token = Token::DIV;
}
break;
case '&':
// & && &=
Advance();
if (c0_ == '&') {
token = Select(Token::AND);
} else if (c0_ == '=') {
token = Select(Token::ASSIGN_BIT_AND);
} else {
token = Token::BIT_AND;
}
break;
case '|':
// | || |=
Advance();
if (c0_ == '|') {
token = Select(Token::OR);
} else if (c0_ == '=') {
token = Select(Token::ASSIGN_BIT_OR);
} else {
token = Token::BIT_OR;
}
break;
case '^':
// ^ ^=
token = Select('=', Token::ASSIGN_BIT_XOR, Token::BIT_XOR);
break;
case '.':
// . Number
Advance();
if (IsDecimalDigit(c0_)) {
token = ScanNumber(true);
} else {
token = Token::PERIOD;
}
break;
case ':':
token = Select(Token::COLON);
break;
case ';':
token = Select(Token::SEMICOLON);
break;
case ',':
token = Select(Token::COMMA);
break;
case '(':
token = Select(Token::LPAREN);
break;
case ')':
token = Select(Token::RPAREN);
break;
case '[':
token = Select(Token::LBRACK);
break;
case ']':
token = Select(Token::RBRACK);
break;
case '{':
token = Select(Token::LBRACE);
break;
case '}':
token = Select(Token::RBRACE);
break;
case '?':
token = Select(Token::CONDITIONAL);
break;
case '~':
token = Select(Token::BIT_NOT);
break;
default:
if (unicode_cache_->IsIdentifierStart(c0_)) {
token = ScanIdentifierOrKeyword();
} else if (IsDecimalDigit(c0_)) {
token = ScanNumber(false);
} else if (SkipWhiteSpace()) {
token = Token::WHITESPACE;
} else if (c0_ < 0) {
token = Token::EOS;
} else {
token = Select(Token::ILLEGAL);
}
break;
}
// Continue scanning for tokens as long as we're just skipping
// whitespace.
} while (token == Token::WHITESPACE);
next_.location.end_pos = source_pos();
next_.token = token;
}
void JavaScriptScanner::SeekForward(int pos) {
// After this call, we will have the token at the given position as
// the "next" token. The "current" token will be invalid.
if (pos == next_.location.beg_pos) return;
int current_pos = source_pos();
ASSERT_EQ(next_.location.end_pos, current_pos);
// Positions inside the lookahead token aren't supported.
ASSERT(pos >= current_pos);
if (pos != current_pos) {
source_->SeekForward(pos - source_->pos());
Advance();
// This function is only called to seek to the location
// of the end of a function (at the "}" token). It doesn't matter
// whether there was a line terminator in the part we skip.
has_line_terminator_before_next_ = false;
}
Scan();
}
void JavaScriptScanner::ScanEscape() {
uc32 c = c0_;
Advance();
// Skip escaped newlines.
if (unicode_cache_->IsLineTerminator(c)) {
// Allow CR+LF newlines in multiline string literals.
if (IsCarriageReturn(c) && IsLineFeed(c0_)) Advance();
// Allow LF+CR newlines in multiline string literals.
if (IsLineFeed(c) && IsCarriageReturn(c0_)) Advance();
return;
}
switch (c) {
case '\'': // fall through
case '"' : // fall through
case '\\': break;
case 'b' : c = '\b'; break;
case 'f' : c = '\f'; break;
case 'n' : c = '\n'; break;
case 'r' : c = '\r'; break;
case 't' : c = '\t'; break;
case 'u' : c = ScanHexEscape(c, 4); break;
case 'v' : c = '\v'; break;
case 'x' : c = ScanHexEscape(c, 2); break;
case '0' : // fall through
case '1' : // fall through
case '2' : // fall through
case '3' : // fall through
case '4' : // fall through
case '5' : // fall through
case '6' : // fall through
case '7' : c = ScanOctalEscape(c, 2); break;
}
// According to ECMA-262, 3rd, 7.8.4 (p 18ff) these
// should be illegal, but they are commonly handled
// as non-escaped characters by JS VMs.
AddLiteralChar(c);
}
Token::Value JavaScriptScanner::ScanString() {
uc32 quote = c0_;
Advance(); // consume quote
LiteralScope literal(this);
while (c0_ != quote && c0_ >= 0
&& !unicode_cache_->IsLineTerminator(c0_)) {
uc32 c = c0_;
Advance();
if (c == '\\') {
if (c0_ < 0) return Token::ILLEGAL;
ScanEscape();
} else {
AddLiteralChar(c);
}
}
if (c0_ != quote) return Token::ILLEGAL;
literal.Complete();
Advance(); // consume quote
return Token::STRING;
}
void JavaScriptScanner::ScanDecimalDigits() {
while (IsDecimalDigit(c0_))
AddLiteralCharAdvance();
}
Token::Value JavaScriptScanner::ScanNumber(bool seen_period) {
ASSERT(IsDecimalDigit(c0_)); // the first digit of the number or the fraction
enum { DECIMAL, HEX, OCTAL } kind = DECIMAL;
LiteralScope literal(this);
if (seen_period) {
// we have already seen a decimal point of the float
AddLiteralChar('.');
ScanDecimalDigits(); // we know we have at least one digit
} else {
// if the first character is '0' we must check for octals and hex
if (c0_ == '0') {
AddLiteralCharAdvance();
// either 0, 0exxx, 0Exxx, 0.xxx, an octal number, or a hex number
if (c0_ == 'x' || c0_ == 'X') {
// hex number
kind = HEX;
AddLiteralCharAdvance();
if (!IsHexDigit(c0_)) {
// we must have at least one hex digit after 'x'/'X'
return Token::ILLEGAL;
}
while (IsHexDigit(c0_)) {
AddLiteralCharAdvance();
}
} else if ('0' <= c0_ && c0_ <= '7') {
// (possible) octal number
kind = OCTAL;
while (true) {
if (c0_ == '8' || c0_ == '9') {
kind = DECIMAL;
break;
}
if (c0_ < '0' || '7' < c0_) {
// Octal literal finished.
octal_pos_ = next_.location.beg_pos;
break;
}
AddLiteralCharAdvance();
}
}
}
// Parse decimal digits and allow trailing fractional part.
if (kind == DECIMAL) {
ScanDecimalDigits(); // optional
if (c0_ == '.') {
AddLiteralCharAdvance();
ScanDecimalDigits(); // optional
}
}
}
// scan exponent, if any
if (c0_ == 'e' || c0_ == 'E') {
ASSERT(kind != HEX); // 'e'/'E' must be scanned as part of the hex number
if (kind == OCTAL) return Token::ILLEGAL; // no exponent for octals allowed
// scan exponent
AddLiteralCharAdvance();
if (c0_ == '+' || c0_ == '-')
AddLiteralCharAdvance();
if (!IsDecimalDigit(c0_)) {
// we must have at least one decimal digit after 'e'/'E'
return Token::ILLEGAL;
}
ScanDecimalDigits();
}
// The source character immediately following a numeric literal must
// not be an identifier start or a decimal digit; see ECMA-262
// section 7.8.3, page 17 (note that we read only one decimal digit
// if the value is 0).
if (IsDecimalDigit(c0_) || unicode_cache_->IsIdentifierStart(c0_))
return Token::ILLEGAL;
literal.Complete();
return Token::NUMBER;
}
uc32 JavaScriptScanner::ScanIdentifierUnicodeEscape() {
Advance();
if (c0_ != 'u') return unibrow::Utf8::kBadChar;
Advance();
uc32 c = ScanHexEscape('u', 4);
// We do not allow a unicode escape sequence to start another
// unicode escape sequence.
if (c == '\\') return unibrow::Utf8::kBadChar;
return c;
}
Token::Value JavaScriptScanner::ScanIdentifierOrKeyword() {
ASSERT(unicode_cache_->IsIdentifierStart(c0_));
LiteralScope literal(this);
KeywordMatcher keyword_match;
// Scan identifier start character.
if (c0_ == '\\') {
uc32 c = ScanIdentifierUnicodeEscape();
// Only allow legal identifier start characters.
if (!unicode_cache_->IsIdentifierStart(c)) return Token::ILLEGAL;
AddLiteralChar(c);
return ScanIdentifierSuffix(&literal);
}
uc32 first_char = c0_;
Advance();
AddLiteralChar(first_char);
if (!keyword_match.AddChar(first_char)) {
return ScanIdentifierSuffix(&literal);
}
// Scan the rest of the identifier characters.
while (unicode_cache_->IsIdentifierPart(c0_)) {
if (c0_ != '\\') {
uc32 next_char = c0_;
Advance();
AddLiteralChar(next_char);
if (keyword_match.AddChar(next_char)) continue;
}
// Fallthrough if no loner able to complete keyword.
return ScanIdentifierSuffix(&literal);
}
literal.Complete();
return keyword_match.token();
}
Token::Value JavaScriptScanner::ScanIdentifierSuffix(LiteralScope* literal) {
// Scan the rest of the identifier characters.
while (unicode_cache_->IsIdentifierPart(c0_)) {
if (c0_ == '\\') {
uc32 c = ScanIdentifierUnicodeEscape();
// Only allow legal identifier part characters.
if (!unicode_cache_->IsIdentifierPart(c)) return Token::ILLEGAL;
AddLiteralChar(c);
} else {
AddLiteralChar(c0_);
Advance();
}
}
literal->Complete();
return Token::IDENTIFIER;
}
bool JavaScriptScanner::ScanRegExpPattern(bool seen_equal) {
// Scan: ('/' | '/=') RegularExpressionBody '/' RegularExpressionFlags
bool in_character_class = false;
// Previous token is either '/' or '/=', in the second case, the
// pattern starts at =.
next_.location.beg_pos = source_pos() - (seen_equal ? 2 : 1);
next_.location.end_pos = source_pos() - (seen_equal ? 1 : 0);
// Scan regular expression body: According to ECMA-262, 3rd, 7.8.5,
// the scanner should pass uninterpreted bodies to the RegExp
// constructor.
LiteralScope literal(this);
if (seen_equal)
AddLiteralChar('=');
while (c0_ != '/' || in_character_class) {
if (unicode_cache_->IsLineTerminator(c0_) || c0_ < 0) return false;
if (c0_ == '\\') { // Escape sequence.
AddLiteralCharAdvance();
if (unicode_cache_->IsLineTerminator(c0_) || c0_ < 0) return false;
AddLiteralCharAdvance();
// If the escape allows more characters, i.e., \x??, \u????, or \c?,
// only "safe" characters are allowed (letters, digits, underscore),
// otherwise the escape isn't valid and the invalid character has
// its normal meaning. I.e., we can just continue scanning without
// worrying whether the following characters are part of the escape
// or not, since any '/', '\\' or '[' is guaranteed to not be part
// of the escape sequence.
} else { // Unescaped character.
if (c0_ == '[') in_character_class = true;
if (c0_ == ']') in_character_class = false;
AddLiteralCharAdvance();
}
}
Advance(); // consume '/'
literal.Complete();
return true;
}
bool JavaScriptScanner::ScanRegExpFlags() {
// Scan regular expression flags.
LiteralScope literal(this);
while (unicode_cache_->IsIdentifierPart(c0_)) {
if (c0_ == '\\') {
uc32 c = ScanIdentifierUnicodeEscape();
if (c != static_cast<uc32>(unibrow::Utf8::kBadChar)) {
// We allow any escaped character, unlike the restriction on
// IdentifierPart when it is used to build an IdentifierName.
AddLiteralChar(c);
continue;
}
}
AddLiteralCharAdvance();
}
literal.Complete();
next_.location.end_pos = source_pos() - 1;
return true;
}
// ----------------------------------------------------------------------------
// Keyword Matcher
KeywordMatcher::FirstState KeywordMatcher::first_states_[] = {
{ "break", KEYWORD_PREFIX, Token::BREAK },
{ NULL, C, Token::ILLEGAL },
{ NULL, D, Token::ILLEGAL },
{ NULL, E, Token::ILLEGAL },
{ NULL, F, Token::ILLEGAL },
{ NULL, UNMATCHABLE, Token::ILLEGAL },
{ NULL, UNMATCHABLE, Token::ILLEGAL },
{ NULL, I, Token::ILLEGAL },
{ NULL, UNMATCHABLE, Token::ILLEGAL },
{ NULL, UNMATCHABLE, Token::ILLEGAL },
{ "let", KEYWORD_PREFIX, Token::FUTURE_RESERVED_WORD },
{ NULL, UNMATCHABLE, Token::ILLEGAL },
{ NULL, N, Token::ILLEGAL },
{ NULL, UNMATCHABLE, Token::ILLEGAL },
{ NULL, P, Token::ILLEGAL },
{ NULL, UNMATCHABLE, Token::ILLEGAL },
{ "return", KEYWORD_PREFIX, Token::RETURN },
{ NULL, S, Token::ILLEGAL },
{ NULL, T, Token::ILLEGAL },
{ NULL, UNMATCHABLE, Token::ILLEGAL },
{ NULL, V, Token::ILLEGAL },
{ NULL, W, Token::ILLEGAL },
{ NULL, UNMATCHABLE, Token::ILLEGAL },
{ "yield", KEYWORD_PREFIX, Token::FUTURE_RESERVED_WORD }
};
void KeywordMatcher::Step(unibrow::uchar input) {
switch (state_) {
case INITIAL: {
// matching the first character is the only state with significant fanout.
// Match only lower-case letters in range 'b'..'y'.
unsigned int offset = input - kFirstCharRangeMin;
if (offset < kFirstCharRangeLength) {
state_ = first_states_[offset].state;
if (state_ == KEYWORD_PREFIX) {
keyword_ = first_states_[offset].keyword;
counter_ = 1;
keyword_token_ = first_states_[offset].token;
}
return;
}
break;
}
case KEYWORD_PREFIX:
if (static_cast<unibrow::uchar>(keyword_[counter_]) == input) {
counter_++;
if (keyword_[counter_] == '\0') {
state_ = KEYWORD_MATCHED;
token_ = keyword_token_;
}
return;
}
break;
case KEYWORD_MATCHED:
token_ = Token::IDENTIFIER;
break;
case C:
if (MatchState(input, 'a', CA)) return;
if (MatchKeywordStart(input, "class", 1,
Token::FUTURE_RESERVED_WORD)) return;
if (MatchState(input, 'o', CO)) return;
break;
case CA:
if (MatchKeywordStart(input, "case", 2, Token::CASE)) return;
if (MatchKeywordStart(input, "catch", 2, Token::CATCH)) return;
break;
case CO:
if (MatchState(input, 'n', CON)) return;
break;
case CON:
if (MatchKeywordStart(input, "const", 3, Token::CONST)) return;
if (MatchKeywordStart(input, "continue", 3, Token::CONTINUE)) return;
break;
case D:
if (MatchState(input, 'e', DE)) return;
if (MatchKeyword(input, 'o', KEYWORD_MATCHED, Token::DO)) return;
break;
case DE:
if (MatchKeywordStart(input, "debugger", 2, Token::DEBUGGER)) return;
if (MatchKeywordStart(input, "default", 2, Token::DEFAULT)) return;
if (MatchKeywordStart(input, "delete", 2, Token::DELETE)) return;
break;
case E:
if (MatchKeywordStart(input, "else", 1, Token::ELSE)) return;
if (MatchKeywordStart(input, "enum", 1,
Token::FUTURE_RESERVED_WORD)) return;
if (MatchState(input, 'x', EX)) return;
break;
case EX:
if (MatchKeywordStart(input, "export", 2,
Token::FUTURE_RESERVED_WORD)) return;
if (MatchKeywordStart(input, "extends", 2,
Token::FUTURE_RESERVED_WORD)) return;
break;
case F:
if (MatchKeywordStart(input, "false", 1, Token::FALSE_LITERAL)) return;
if (MatchKeywordStart(input, "finally", 1, Token::FINALLY)) return;
if (MatchKeywordStart(input, "for", 1, Token::FOR)) return;
if (MatchKeywordStart(input, "function", 1, Token::FUNCTION)) return;
break;
case I:
if (MatchKeyword(input, 'f', KEYWORD_MATCHED, Token::IF)) return;
if (MatchState(input, 'm', IM)) return;
if (MatchKeyword(input, 'n', IN, Token::IN)) return;
break;
case IM:
if (MatchState(input, 'p', IMP)) return;
break;
case IMP:
if (MatchKeywordStart(input, "implements", 3,
Token::FUTURE_RESERVED_WORD )) return;
if (MatchKeywordStart(input, "import", 3,
Token::FUTURE_RESERVED_WORD)) return;
break;
case IN:
token_ = Token::IDENTIFIER;
if (MatchKeywordStart(input, "interface", 2,
Token::FUTURE_RESERVED_WORD)) return;
if (MatchKeywordStart(input, "instanceof", 2, Token::INSTANCEOF)) return;
break;
case N:
if (MatchKeywordStart(input, "native", 1, Token::NATIVE)) return;
if (MatchKeywordStart(input, "new", 1, Token::NEW)) return;
if (MatchKeywordStart(input, "null", 1, Token::NULL_LITERAL)) return;
break;
case P:
if (MatchKeywordStart(input, "package", 1,
Token::FUTURE_RESERVED_WORD)) return;
if (MatchState(input, 'r', PR)) return;
if (MatchKeywordStart(input, "public", 1,
Token::FUTURE_RESERVED_WORD)) return;
break;
case PR:
if (MatchKeywordStart(input, "private", 2,
Token::FUTURE_RESERVED_WORD)) return;
if (MatchKeywordStart(input, "protected", 2,
Token::FUTURE_RESERVED_WORD)) return;
break;
case S:
if (MatchKeywordStart(input, "static", 1,
Token::FUTURE_RESERVED_WORD)) return;
if (MatchKeywordStart(input, "super", 1,
Token::FUTURE_RESERVED_WORD)) return;
if (MatchKeywordStart(input, "switch", 1,
Token::SWITCH)) return;
break;
case T:
if (MatchState(input, 'h', TH)) return;
if (MatchState(input, 'r', TR)) return;
if (MatchKeywordStart(input, "typeof", 1, Token::TYPEOF)) return;
break;
case TH:
if (MatchKeywordStart(input, "this", 2, Token::THIS)) return;
if (MatchKeywordStart(input, "throw", 2, Token::THROW)) return;
break;
case TR:
if (MatchKeywordStart(input, "true", 2, Token::TRUE_LITERAL)) return;
if (MatchKeyword(input, 'y', KEYWORD_MATCHED, Token::TRY)) return;
break;
case V:
if (MatchKeywordStart(input, "var", 1, Token::VAR)) return;
if (MatchKeywordStart(input, "void", 1, Token::VOID)) return;
break;
case W:
if (MatchKeywordStart(input, "while", 1, Token::WHILE)) return;
if (MatchKeywordStart(input, "with", 1, Token::WITH)) return;
break;
case UNMATCHABLE:
break;
}
// On fallthrough, it's a failure.
state_ = UNMATCHABLE;
}
} } // namespace v8::internal