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erichocean/jsparse.js

Created October 21, 2008 21:35
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jsparse.js
/* vim: set sw=4 ts=8 et tw=78: */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is the Narcissus JavaScript engine.
*
* The Initial Developer of the Original Code is
* Brendan Eich <[email protected]>.
* Portions created by the Initial Developer are Copyright (C) 2004
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
/*
* Narcissus - JS implemented in JS.
*
* Lexical scanner and parser.
*/
// Build a regexp that recognizes operators and punctuators (except newline).
var opRegExpSrc = "^";
for (i in opTypeNames) {
if (i == '\n')
continue;
if (opRegExpSrc != "^")
opRegExpSrc += "|^";
opRegExpSrc += i.replace(/[?|^&(){}\[\]+\-*\/\.]/g, "\\$&");
}
var opRegExp = new RegExp(opRegExpSrc);
// A regexp to match floating point literals (but not integer literals).
var fpRegExp = /^\d+\.\d*(?:[eE][-+]?\d+)?|^\d+(?:\.\d*)?[eE][-+]?\d+|^\.\d+(?:[eE][-+]?\d+)?/;
// A regexp to match regexp literals.
var reRegExp = /^\/((?:\\.|\[(?:\\.|[^\]])*\]|[^\/])+)\/([gimy]*)/;
function Tokenizer(s, f, l) {
this.cursor = 0;
this.source = String(s);
this.tokens = [];
this.tokenIndex = 0;
this.lookahead = 0;
this.scanNewlines = false;
this.scanOperand = true;
this.filename = f || "";
this.lineno = l || 1;
}
Tokenizer.prototype = {
get input() {
return this.source.substring(this.cursor);
},
get done() {
return this.peek() == END;
},
get token() {
return this.tokens[this.tokenIndex];
},
match: function (tt) {
return this.get() == tt || this.unget();
},
mustMatch: function (tt) {
if (!this.match(tt))
throw this.newSyntaxError("Missing " + tokens[tt].toLowerCase());
return this.token;
},
peek: function () {
var tt, next;
if (this.lookahead) {
next = this.tokens[(this.tokenIndex + this.lookahead) & 3];
if (this.scanNewlines && next.lineno != this.lineno)
tt = NEWLINE;
else
tt = next.type;
} else {
tt = this.get();
this.unget();
}
return tt;
},
peekOnSameLine: function () {
this.scanNewlines = true;
var tt = this.peek();
this.scanNewlines = false;
return tt;
},
get: function () {
var token;
while (this.lookahead) {
--this.lookahead;
this.tokenIndex = (this.tokenIndex + 1) & 3;
token = this.tokens[this.tokenIndex];
if (token.type != NEWLINE || this.scanNewlines)
return token.type;
}
for (;;) {
var input = this.input;
var match = (this.scanNewlines ? /^[ \t]+/ : /^\s+/)(input);
if (match) {
var spaces = match[0];
this.cursor += spaces.length;
var newlines = spaces.match(/\n/g);
if (newlines)
this.lineno += newlines.length;
input = this.input;
}
if (!(match = /^\/(?:\*(?:.|\n)*?\*\/|\/.*)/(input)))
break;
var comment = match[0];
this.cursor += comment.length;
newlines = comment.match(/\n/g);
if (newlines)
this.lineno += newlines.length
}
this.tokenIndex = (this.tokenIndex + 1) & 3;
token = this.tokens[this.tokenIndex];
if (!token)
this.tokens[this.tokenIndex] = token = {};
if (!input)
return token.type = END;
if ((match = fpRegExp(input))) {
token.type = NUMBER;
token.value = parseFloat(match[0]);
} else if ((match = /^0[xX][\da-fA-F]+|^0[0-7]*|^\d+/(input))) {
token.type = NUMBER;
token.value = parseInt(match[0]);
} else if ((match = /^[$_\w]+/(input))) { // FIXME no ES3 unicode
var id = match[0];
token.type = keywords[id] || IDENTIFIER;
token.value = id;
} else if ((match = /^"(?:\\.|[^"])*"|^'(?:\\.|[^'])*'/(input))) { //"){
token.type = STRING;
token.value = eval(match[0]);
} else if (this.scanOperand && (match = reRegExp(input))) {
token.type = REGEXP;
token.value = new RegExp(match[1], match[2]);
} else if ((match = opRegExp(input))) {
var op = match[0];
if (assignOps[op] && input[op.length] == '=') {
token.type = ASSIGN;
token.assignOp = GLOBAL[opTypeNames[op]];
match[0] += '=';
} else {
token.type = GLOBAL[opTypeNames[op]];
if (this.scanOperand &&
(token.type == PLUS || token.type == MINUS)) {
token.type += UNARY_PLUS - PLUS;
}
token.assignOp = null;
}
token.value = op;
} else if (this.scanNewlines && (match = /^\n/(input))) {
token.type = NEWLINE;
} else {
throw this.newSyntaxError("Illegal token");
}
token.start = this.cursor;
this.cursor += match[0].length;
token.end = this.cursor;
token.lineno = this.lineno;
return token.type;
},
unget: function () {
if (++this.lookahead == 4) throw "PANIC: too much lookahead!";
this.tokenIndex = (this.tokenIndex - 1) & 3;
},
newSyntaxError: function (m) {
var e = new SyntaxError(m, this.filename, this.lineno);
e.source = this.source;
e.cursor = this.cursor;
return e;
}
};
function CompilerContext(inFunction) {
this.inFunction = inFunction;
this.stmtStack = [];
this.funDecls = [];
this.varDecls = [];
}
var CCp = CompilerContext.prototype;
CCp.bracketLevel = CCp.curlyLevel = CCp.parenLevel = CCp.hookLevel = 0;
CCp.ecmaStrictMode = CCp.inForLoopInit = false;
function Script(t, x) {
var n = Statements(t, x);
n.type = SCRIPT;
n.funDecls = x.funDecls;
n.varDecls = x.varDecls;
return n;
}
// Node extends Array, which we extend slightly with a top-of-stack method.
Array.prototype.__defineProperty__(
'top',
function () {
return this.length && this[this.length-1];
},
false, false, true
);
function Node(t, type) {
var token = t.token;
if (token) {
this.type = type || token.type;
this.value = token.value;
this.lineno = token.lineno;
this.start = token.start;
this.end = token.end;
} else {
this.type = type;
this.lineno = t.lineno;
}
this.tokenizer = t;
for (var i = 2; i < arguments.length; i++)
this.push(arguments[i]);
}
var Np = Node.prototype = new Array;
Np.constructor = Node;
Np.toSource = Object.prototype.toSource;
// Always use push to add operands to an expression, to update start and end.
Np.push = function (kid) {
if (kid.start < this.start)
this.start = kid.start;
if (this.end < kid.end)
this.end = kid.end;
return Array.prototype.push.call(this, kid);
}
Node.indentLevel = 0;
function tokenstr(tt) {
var t = tokens[tt];
return /^\W/.test(t) ? opTypeNames[t] : t.toUpperCase();
}
Np.toString = function () {
var a = [];
for (var i in this) {
if (this.hasOwnProperty(i) && i != 'type' && i != 'target')
a.push({id: i, value: this[i]});
}
a.sort(function (a,b) { return (a.id < b.id) ? -1 : 1; });
const INDENTATION = " ";
var n = ++Node.indentLevel;
var s = "{\n" + INDENTATION.repeat(n) + "type: " + tokenstr(this.type);
for (i = 0; i < a.length; i++)
s += ",\n" + INDENTATION.repeat(n) + a[i].id + ": " + a[i].value;
n = --Node.indentLevel;
s += "\n" + INDENTATION.repeat(n) + "}";
return s;
}
Np.getSource = function () {
return this.tokenizer.source.slice(this.start, this.end);
};
Np.__defineGetter__('filename',
function () { return this.tokenizer.filename; });
String.prototype.__defineProperty__(
'repeat',
function (n) {
var s = "", t = this + s;
while (--n >= 0)
s += t;
return s;
},
false, false, true
);
// Statement stack and nested statement handler.
function nest(t, x, node, func, end) {
x.stmtStack.push(node);
var n = func(t, x);
x.stmtStack.pop();
end && t.mustMatch(end);
return n;
}
function Statements(t, x) {
var n = new Node(t, BLOCK);
x.stmtStack.push(n);
while (!t.done && t.peek() != RIGHT_CURLY)
n.push(Statement(t, x));
x.stmtStack.pop();
return n;
}
function Block(t, x) {
t.mustMatch(LEFT_CURLY);
var n = Statements(t, x);
t.mustMatch(RIGHT_CURLY);
return n;
}
const DECLARED_FORM = 0, EXPRESSED_FORM = 1, STATEMENT_FORM = 2;
function Statement(t, x) {
var i, label, n, n2, ss, tt = t.get();
// Cases for statements ending in a right curly return early, avoiding the
// common semicolon insertion magic after this switch.
switch (tt) {
case FUNCTION:
return FunctionDefinition(t, x, true,
(x.stmtStack.length > 1)
? STATEMENT_FORM
: DECLARED_FORM);
case LEFT_CURLY:
n = Statements(t, x);
t.mustMatch(RIGHT_CURLY);
return n;
case IF:
n = new Node(t);
n.condition = ParenExpression(t, x);
x.stmtStack.push(n);
n.thenPart = Statement(t, x);
n.elsePart = t.match(ELSE) ? Statement(t, x) : null;
x.stmtStack.pop();
return n;
case SWITCH:
n = new Node(t);
t.mustMatch(LEFT_PAREN);
n.discriminant = Expression(t, x);
t.mustMatch(RIGHT_PAREN);
n.cases = [];
n.defaultIndex = -1;
x.stmtStack.push(n);
t.mustMatch(LEFT_CURLY);
while ((tt = t.get()) != RIGHT_CURLY) {
switch (tt) {
case DEFAULT:
if (n.defaultIndex >= 0)
throw t.newSyntaxError("More than one switch default");
// FALL THROUGH
case CASE:
n2 = new Node(t);
if (tt == DEFAULT)
n.defaultIndex = n.cases.length;
else
n2.caseLabel = Expression(t, x, COLON);
break;
default:
throw t.newSyntaxError("Invalid switch case");
}
t.mustMatch(COLON);
n2.statements = new Node(t, BLOCK);
while ((tt=t.peek()) != CASE && tt != DEFAULT && tt != RIGHT_CURLY)
n2.statements.push(Statement(t, x));
n.cases.push(n2);
}
x.stmtStack.pop();
return n;
case FOR:
n = new Node(t);
n.isLoop = true;
t.mustMatch(LEFT_PAREN);
if ((tt = t.peek()) != SEMICOLON) {
x.inForLoopInit = true;
if (tt == VAR || tt == CONST) {
t.get();
n2 = Variables(t, x);
} else {
n2 = Expression(t, x);
}
x.inForLoopInit = false;
}
if (n2 && t.match(IN)) {
n.type = FOR_IN;
if (n2.type == VAR) {
if (n2.length != 1) {
throw new SyntaxError("Invalid for..in left-hand side",
t.filename, n2.lineno);
}
// NB: n2[0].type == IDENTIFIER and n2[0].value == n2[0].name.
n.iterator = n2[0];
n.varDecl = n2;
} else {
n.iterator = n2;
n.varDecl = null;
}
n.object = Expression(t, x);
} else {
n.setup = n2 || null;
t.mustMatch(SEMICOLON);
n.condition = (t.peek() == SEMICOLON) ? null : Expression(t, x);
t.mustMatch(SEMICOLON);
n.update = (t.peek() == RIGHT_PAREN) ? null : Expression(t, x);
}
t.mustMatch(RIGHT_PAREN);
n.body = nest(t, x, n, Statement);
return n;
case WHILE:
n = new Node(t);
n.isLoop = true;
n.condition = ParenExpression(t, x);
n.body = nest(t, x, n, Statement);
return n;
case DO:
n = new Node(t);
n.isLoop = true;
n.body = nest(t, x, n, Statement, WHILE);
n.condition = ParenExpression(t, x);
if (!x.ecmaStrictMode) {
// <script language="JavaScript"> (without version hints) may need
// automatic semicolon insertion without a newline after do-while.
// See http://bugzilla.mozilla.org/show_bug.cgi?id=238945.
t.match(SEMICOLON);
return n;
}
break;
case BREAK:
case CONTINUE:
n = new Node(t);
if (t.peekOnSameLine() == IDENTIFIER) {
t.get();
n.label = t.token.value;
}
ss = x.stmtStack;
i = ss.length;
label = n.label;
if (label) {
do {
if (--i < 0)
throw t.newSyntaxError("Label not found");
} while (ss[i].label != label);
} else {
do {
if (--i < 0) {
throw t.newSyntaxError("Invalid " + ((tt == BREAK)
? "break"
: "continue"));
}
} while (!ss[i].isLoop && (tt != BREAK || ss[i].type != SWITCH));
}
n.target = ss[i];
break;
case TRY:
n = new Node(t);
n.tryBlock = Block(t, x);
n.catchClauses = [];
while (t.match(CATCH)) {
n2 = new Node(t);
t.mustMatch(LEFT_PAREN);
n2.varName = t.mustMatch(IDENTIFIER).value;
if (t.match(IF)) {
if (x.ecmaStrictMode)
throw t.newSyntaxError("Illegal catch guard");
if (n.catchClauses.length && !n.catchClauses.top().guard)
throw t.newSyntaxError("Guarded catch after unguarded");
n2.guard = Expression(t, x);
} else {
n2.guard = null;
}
t.mustMatch(RIGHT_PAREN);
n2.block = Block(t, x);
n.catchClauses.push(n2);
}
if (t.match(FINALLY))
n.finallyBlock = Block(t, x);
if (!n.catchClauses.length && !n.finallyBlock)
throw t.newSyntaxError("Invalid try statement");
return n;
case CATCH:
case FINALLY:
throw t.newSyntaxError(tokens[tt] + " without preceding try");
case THROW:
n = new Node(t);
n.exception = Expression(t, x);
break;
case RETURN:
if (!x.inFunction)
throw t.newSyntaxError("Invalid return");
n = new Node(t);
tt = t.peekOnSameLine();
if (tt != END && tt != NEWLINE && tt != SEMICOLON && tt != RIGHT_CURLY)
n.value = Expression(t, x);
break;
case WITH:
n = new Node(t);
n.object = ParenExpression(t, x);
n.body = nest(t, x, n, Statement);
return n;
case VAR:
case CONST:
n = Variables(t, x);
break;
case DEBUGGER:
n = new Node(t);
break;
case NEWLINE:
case SEMICOLON:
n = new Node(t, SEMICOLON);
n.expression = null;
return n;
default:
if (tt == IDENTIFIER) {
t.scanOperand = false;
tt = t.peek();
t.scanOperand = true;
if (tt == COLON) {
label = t.token.value;
ss = x.stmtStack;
for (i = ss.length-1; i >= 0; --i) {
if (ss[i].label == label)
throw t.newSyntaxError("Duplicate label");
}
t.get();
n = new Node(t, LABEL);
n.label = label;
n.statement = nest(t, x, n, Statement);
return n;
}
}
n = new Node(t, SEMICOLON);
t.unget();
n.expression = Expression(t, x);
n.end = n.expression.end;
break;
}
if (t.lineno == t.token.lineno) {
tt = t.peekOnSameLine();
if (tt != END && tt != NEWLINE && tt != SEMICOLON && tt != RIGHT_CURLY)
throw t.newSyntaxError("Missing ; before statement");
}
t.match(SEMICOLON);
return n;
}
function FunctionDefinition(t, x, requireName, functionForm) {
var f = new Node(t);
if (f.type != FUNCTION)
f.type = (f.value == "get") ? GETTER : SETTER;
if (t.match(IDENTIFIER))
f.name = t.token.value;
else if (requireName)
throw t.newSyntaxError("Missing function identifier");
t.mustMatch(LEFT_PAREN);
f.params = [];
var tt;
while ((tt = t.get()) != RIGHT_PAREN) {
if (tt != IDENTIFIER)
throw t.newSyntaxError("Missing formal parameter");
f.params.push(t.token.value);
if (t.peek() != RIGHT_PAREN)
t.mustMatch(COMMA);
}
t.mustMatch(LEFT_CURLY);
var x2 = new CompilerContext(true);
f.body = Script(t, x2);
t.mustMatch(RIGHT_CURLY);
f.end = t.token.end;
f.functionForm = functionForm;
if (functionForm == DECLARED_FORM)
x.funDecls.push(f);
return f;
}
function Variables(t, x) {
var n = new Node(t);
do {
t.mustMatch(IDENTIFIER);
var n2 = new Node(t);
n2.name = n2.value;
if (t.match(ASSIGN)) {
if (t.token.assignOp)
throw t.newSyntaxError("Invalid variable initialization");
n2.initializer = Expression(t, x, COMMA);
}
n2.readOnly = (n.type == CONST);
n.push(n2);
x.varDecls.push(n2);
} while (t.match(COMMA));
return n;
}
function ParenExpression(t, x) {
t.mustMatch(LEFT_PAREN);
var n = Expression(t, x);
t.mustMatch(RIGHT_PAREN);
return n;
}
var opPrecedence = {
SEMICOLON: 0,
COMMA: 1,
ASSIGN: 2, HOOK: 2, COLON: 2,
// The above all have to have the same precedence, see bug 330975.
OR: 4,
AND: 5,
BITWISE_OR: 6,
BITWISE_XOR: 7,
BITWISE_AND: 8,
EQ: 9, NE: 9, STRICT_EQ: 9, STRICT_NE: 9,
LT: 10, LE: 10, GE: 10, GT: 10, IN: 10, INSTANCEOF: 10,
LSH: 11, RSH: 11, URSH: 11,
PLUS: 12, MINUS: 12,
MUL: 13, DIV: 13, MOD: 13,
DELETE: 14, VOID: 14, TYPEOF: 14, // PRE_INCREMENT: 14, PRE_DECREMENT: 14,
NOT: 14, BITWISE_NOT: 14, UNARY_PLUS: 14, UNARY_MINUS: 14,
INCREMENT: 15, DECREMENT: 15, // postfix
NEW: 16,
DOT: 17
};
// Map operator type code to precedence.
for (i in opPrecedence)
opPrecedence[GLOBAL[i]] = opPrecedence[i];
var opArity = {
COMMA: -2,
ASSIGN: 2,
HOOK: 3,
OR: 2,
AND: 2,
BITWISE_OR: 2,
BITWISE_XOR: 2,
BITWISE_AND: 2,
EQ: 2, NE: 2, STRICT_EQ: 2, STRICT_NE: 2,
LT: 2, LE: 2, GE: 2, GT: 2, IN: 2, INSTANCEOF: 2,
LSH: 2, RSH: 2, URSH: 2,
PLUS: 2, MINUS: 2,
MUL: 2, DIV: 2, MOD: 2,
DELETE: 1, VOID: 1, TYPEOF: 1, // PRE_INCREMENT: 1, PRE_DECREMENT: 1,
NOT: 1, BITWISE_NOT: 1, UNARY_PLUS: 1, UNARY_MINUS: 1,
INCREMENT: 1, DECREMENT: 1, // postfix
NEW: 1, NEW_WITH_ARGS: 2, DOT: 2, INDEX: 2, CALL: 2,
ARRAY_INIT: 1, OBJECT_INIT: 1, GROUP: 1
};
// Map operator type code to arity.
for (i in opArity)
opArity[GLOBAL[i]] = opArity[i];
function Expression(t, x, stop) {
var n, id, tt, operators = [], operands = [];
var bl = x.bracketLevel, cl = x.curlyLevel, pl = x.parenLevel,
hl = x.hookLevel;
function reduce() {
var n = operators.pop();
var op = n.type;
var arity = opArity[op];
if (arity == -2) {
// Flatten left-associative trees.
var left = operands.length >= 2 && operands[operands.length-2];
if (left.type == op) {
var right = operands.pop();
left.push(right);
return left;
}
arity = 2;
}
// Always use push to add operands to n, to update start and end.
var a = operands.splice(operands.length - arity);
for (var i = 0; i < arity; i++)
n.push(a[i]);
// Include closing bracket or postfix operator in [start,end).
if (n.end < t.token.end)
n.end = t.token.end;
operands.push(n);
return n;
}
loop:
while ((tt = t.get()) != END) {
if (tt == stop &&
x.bracketLevel == bl && x.curlyLevel == cl && x.parenLevel == pl &&
x.hookLevel == hl) {
// Stop only if tt matches the optional stop parameter, and that
// token is not quoted by some kind of bracket.
break;
}
switch (tt) {
case SEMICOLON:
// NB: cannot be empty, Statement handled that.
break loop;
case ASSIGN:
case HOOK:
case COLON:
if (t.scanOperand)
break loop;
// Use >, not >=, for right-associative ASSIGN and HOOK/COLON.
while (opPrecedence[operators.top().type] > opPrecedence[tt] ||
(tt == COLON && operators.top().type == ASSIGN)) {
reduce();
}
if (tt == COLON) {
n = operators.top();
if (n.type != HOOK)
throw t.newSyntaxError("Invalid label");
--x.hookLevel;
} else {
operators.push(new Node(t));
if (tt == ASSIGN)
operands.top().assignOp = t.token.assignOp;
else
++x.hookLevel; // tt == HOOK
}
t.scanOperand = true;
break;
case IN:
// An in operator should not be parsed if we're parsing the head of
// a for (...) loop, unless it is in the then part of a conditional
// expression, or parenthesized somehow.
if (x.inForLoopInit && !x.hookLevel &&
!x.bracketLevel && !x.curlyLevel && !x.parenLevel) {
break loop;
}
// FALL THROUGH
case COMMA:
// Treat comma as left-associative so reduce can fold left-heavy
// COMMA trees into a single array.
// FALL THROUGH
case OR:
case AND:
case BITWISE_OR:
case BITWISE_XOR:
case BITWISE_AND:
case EQ: case NE: case STRICT_EQ: case STRICT_NE:
case LT: case LE: case GE: case GT:
case INSTANCEOF:
case LSH: case RSH: case URSH:
case PLUS: case MINUS:
case MUL: case DIV: case MOD:
case DOT:
if (t.scanOperand)
break loop;
while (opPrecedence[operators.top().type] >= opPrecedence[tt])
reduce();
if (tt == DOT) {
t.mustMatch(IDENTIFIER);
operands.push(new Node(t, DOT, operands.pop(), new Node(t)));
} else {
operators.push(new Node(t));
t.scanOperand = true;
}
break;
case DELETE: case VOID: case TYPEOF:
case NOT: case BITWISE_NOT: case UNARY_PLUS: case UNARY_MINUS:
case NEW:
if (!t.scanOperand)
break loop;
operators.push(new Node(t));
break;
case INCREMENT: case DECREMENT:
if (t.scanOperand) {
operators.push(new Node(t)); // prefix increment or decrement
} else {
// Don't cross a line boundary for postfix {in,de}crement.
if (t.tokens[(t.tokenIndex + t.lookahead - 1) & 3].lineno !=
t.lineno) {
break loop;
}
// Use >, not >=, so postfix has higher precedence than prefix.
while (opPrecedence[operators.top().type] > opPrecedence[tt])
reduce();
n = new Node(t, tt, operands.pop());
n.postfix = true;
operands.push(n);
}
break;
case FUNCTION:
if (!t.scanOperand)
break loop;
operands.push(FunctionDefinition(t, x, false, EXPRESSED_FORM));
t.scanOperand = false;
break;
case NULL: case THIS: case TRUE: case FALSE:
case IDENTIFIER: case NUMBER: case STRING: case REGEXP:
if (!t.scanOperand)
break loop;
operands.push(new Node(t));
t.scanOperand = false;
break;
case LEFT_BRACKET:
if (t.scanOperand) {
// Array initialiser. Parse using recursive descent, as the
// sub-grammar here is not an operator grammar.
n = new Node(t, ARRAY_INIT);
while ((tt = t.peek()) != RIGHT_BRACKET) {
if (tt == COMMA) {
t.get();
n.push(null);
continue;
}
n.push(Expression(t, x, COMMA));
if (!t.match(COMMA))
break;
}
t.mustMatch(RIGHT_BRACKET);
operands.push(n);
t.scanOperand = false;
} else {
// Property indexing operator.
operators.push(new Node(t, INDEX));
t.scanOperand = true;
++x.bracketLevel;
}
break;
case RIGHT_BRACKET:
if (t.scanOperand || x.bracketLevel == bl)
break loop;
while (reduce().type != INDEX)
continue;
--x.bracketLevel;
break;
case LEFT_CURLY:
if (!t.scanOperand)
break loop;
// Object initialiser. As for array initialisers (see above),
// parse using recursive descent.
++x.curlyLevel;
n = new Node(t, OBJECT_INIT);
object_init:
if (!t.match(RIGHT_CURLY)) {
do {
tt = t.get();
if ((t.token.value == "get" || t.token.value == "set") &&
t.peek() == IDENTIFIER) {
if (x.ecmaStrictMode)
throw t.newSyntaxError("Illegal property accessor");
n.push(FunctionDefinition(t, x, true, EXPRESSED_FORM));
} else {
switch (tt) {
case IDENTIFIER:
case NUMBER:
case STRING:
id = new Node(t);
break;
case RIGHT_CURLY:
if (x.ecmaStrictMode)
throw t.newSyntaxError("Illegal trailing ,");
break object_init;
default:
throw t.newSyntaxError("Invalid property name");
}
t.mustMatch(COLON);
n.push(new Node(t, PROPERTY_INIT, id,
Expression(t, x, COMMA)));
}
} while (t.match(COMMA));
t.mustMatch(RIGHT_CURLY);
}
operands.push(n);
t.scanOperand = false;
--x.curlyLevel;
break;
case RIGHT_CURLY:
if (!t.scanOperand && x.curlyLevel != cl)
throw "PANIC: right curly botch";
break loop;
case LEFT_PAREN:
if (t.scanOperand) {
operators.push(new Node(t, GROUP));
} else {
while (opPrecedence[operators.top().type] > opPrecedence[NEW])
reduce();
// Handle () now, to regularize the n-ary case for n > 0.
// We must set scanOperand in case there are arguments and
// the first one is a regexp or unary+/-.
n = operators.top();
t.scanOperand = true;
if (t.match(RIGHT_PAREN)) {
if (n.type == NEW) {
--operators.length;
n.push(operands.pop());
} else {
n = new Node(t, CALL, operands.pop(),
new Node(t, LIST));
}
operands.push(n);
t.scanOperand = false;
break;
}
if (n.type == NEW)
n.type = NEW_WITH_ARGS;
else
operators.push(new Node(t, CALL));
}
++x.parenLevel;
break;
case RIGHT_PAREN:
if (t.scanOperand || x.parenLevel == pl)
break loop;
while ((tt = reduce().type) != GROUP && tt != CALL &&
tt != NEW_WITH_ARGS) {
continue;
}
if (tt != GROUP) {
n = operands.top();
if (n[1].type != COMMA)
n[1] = new Node(t, LIST, n[1]);
else
n[1].type = LIST;
}
--x.parenLevel;
break;
// Automatic semicolon insertion means we may scan across a newline
// and into the beginning of another statement. If so, break out of
// the while loop and let the t.scanOperand logic handle errors.
default:
break loop;
}
}
if (x.hookLevel != hl)
throw t.newSyntaxError("Missing : after ?");
if (x.parenLevel != pl)
throw t.newSyntaxError("Missing ) in parenthetical");
if (x.bracketLevel != bl)
throw t.newSyntaxError("Missing ] in index expression");
if (t.scanOperand)
throw t.newSyntaxError("Missing operand");
// Resume default mode, scanning for operands, not operators.
t.scanOperand = true;
t.unget();
while (operators.length)
reduce();
return operands.pop();
}
function parse(s, f, l) {
var t = new Tokenizer(s, f, l);
var x = new CompilerContext(false);
var n = Script(t, x);
if (!t.done)
throw t.newSyntaxError("Syntax error");
return n;
}
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