update require and luaparse

demo/kitchen-sink/require.js

@@ -1951,12 +1951,13 @@ var requirejs, require, define;
         //This module may not have dependencies
         if (!isArray(deps)) {
             callback = deps;
-            deps = [];
+            deps = null;
         }
 
         //If no name, and callback is a function, then figure out if it a
         //CommonJS thing with dependencies.
-        if (!deps.length && isFunction(callback)) {
+        if (!deps && isFunction(callback)) {
+            deps = [];
             //Remove comments from the callback string,
             //look for require calls, and pull them into the dependencies,
             //but only if there are function args.

lib/ace/mode/lua/luaparse.js

@@ -14,15 +14,20 @@ define(function(require, exports, module) {
 }(this, 'luaparse', function (exports) {
   'use strict';
 
-  exports.version = '0.0.1';
+  exports.version = '0.0.11';
 
   var input, options, length;
 
+  // Options can be set either globally on the parser object through
+  // defaultOptions, or during the parse call.
   var defaultOptions = exports.defaultOptions = {
     // Explicitly tell the parser when the input ends.
       wait: false
     // Store comments as an array in the chunk object.
     , comments: true
+    // Track identifier scopes by adding an isLocal attribute to each
+    // identifier-node.
+    , scope: false
   };
 
   // The available tokens expressed as enum flags so they can be checked with
@@ -30,7 +35,7 @@ define(function(require, exports, module) {
 
   var EOF = 1, StringLiteral = 2, Keyword = 4, Identifier = 8
     , NumericLiteral = 16, Punctuator = 32, BooleanLiteral = 64
-    , NilLiteral = 128;
+    , NilLiteral = 128, VarargLiteral = 256;
 
   // As this parser is a bit different from luas own, the error messages
   // will be different in some situations.
@@ -82,6 +87,13 @@ define(function(require, exports, module) {
         , clauses: clauses
       };
     }
+    , ifClause: function(condition, body) {
+      return {
+          type: 'IfClause'
+        , condition: condition
+        , body: body
+      };
+    }
     , elseifClause: function(condition, body) {
       return {
           type: 'ElseifClause'
@@ -142,12 +154,11 @@ define(function(require, exports, module) {
       };
     }
 
-    , functionStatement: function(identifier, parameters, isVararg, isLocal, body) {
+    , functionStatement: function(identifier, parameters, isLocal, body) {
       return {
           type: 'FunctionDeclaration'
         , identifier: identifier
-        , vararg: isVararg
+        , isLocal: isLocal
-        , local: isLocal
         , parameters: parameters
         , body: body
       };
@@ -187,18 +198,19 @@ define(function(require, exports, module) {
       };
     }
 
-    , literal: function(value, raw) {
+    , literal: function(type, value, raw) {
+      type = (type === StringLiteral) ? 'StringLiteral'
+        : (type === NumericLiteral) ? 'NumericLiteral'
+        : (type === BooleanLiteral) ? 'BooleanLiteral'
+        : (type === NilLiteral) ? 'NilLiteral'
+        : 'VarargLiteral';
+
       return {
-          type: 'Literal'
+          type: type
         , value: value
         , raw: raw
       };
     }
-    , varargLiteral: function() {
-      return {
-          type: 'VarargLiteral'
-      };
-    }
 
     , tableKey: function(key, value) {
       return {
@@ -293,7 +305,14 @@ define(function(require, exports, module) {
   // -------
 
   var slice = Array.prototype.slice
-    , toString = Object.prototype.toString;
+    , toString = Object.prototype.toString
+    // Simple indexOf implementation which only provides what's required.
+    , indexOf = Array.prototype.indexOf || function indexOf(element) {
+      for (var i = 0, length = this.length; i < length; i++) {
+        if (this[i] === element) return i;
+      }
+      return -1;
+    };
 
   // A sprintf implementation using %index (beginning at 1) to input
   // arguments in the format string.
@@ -306,7 +325,6 @@ define(function(require, exports, module) {
   function sprintf(format) {
     var args = slice.call(arguments, 1);
     format = format.replace(/%(\d)/g, function (match, index) {
-      match = ''; // jshint
       return '' + args[index - 1] || '';
     });
     return format;
@@ -455,14 +473,14 @@ define(function(require, exports, module) {
       , range: [index, index]
     };
 
-    var char = input.charCodeAt(index)
+    var character = input.charCodeAt(index)
       , next = input.charCodeAt(index + 1);
 
     // Memorize the range index where the token begins.
     tokenStart = index;
-    if (isIdentifierStart(char)) return scanIdentifierOrKeyword();
+    if (isIdentifierStart(character)) return scanIdentifierOrKeyword();
 
-    switch (char) {
+    switch (character) {
       case 39: case 34: // '"
         return scanStringLiteral();
 
@@ -475,7 +493,7 @@ define(function(require, exports, module) {
         // If the dot is followed by a digit it's a float.
         if (isDecDigit(next)) return scanNumericLiteral();
         if (46 === next) {
-          if (46 === input.charCodeAt(index + 2)) return scanPunctuator('...');
+          if (46 === input.charCodeAt(index + 2)) return scanVarargLiteral();
           return scanPunctuator('..');
         }
         return scanPunctuator('.');
@@ -520,10 +538,10 @@ define(function(require, exports, module) {
 
   function skipWhiteSpace() {
     while (index < length) {
-      var char = input.charCodeAt(index);
+      var character = input.charCodeAt(index);
-      if (isWhiteSpace(char)) {
+      if (isWhiteSpace(character)) {
         index++;
-      } else if (isLineTerminator(char)) {
+      } else if (isLineTerminator(character)) {
         line++;
         lineStart = ++index;
       } else {
@@ -580,26 +598,39 @@ define(function(require, exports, module) {
     };
   }
 
+  // A vararg literal consists of three dots.
+
+  function scanVarargLiteral() {
+    index += 3;
+    return {
+        type: VarargLiteral
+      , value: '...'
+      , line: line
+      , lineStart: lineStart
+      , range: [tokenStart, index]
+    };
+  }
+
   // Find the string literal by matching the delimiter marks used.
 
   function scanStringLiteral() {
     var delimiter = input.charCodeAt(index++)
       , stringStart = index
       , string = ''
-      , char;
+      , character;
 
     while (index < length) {
-      char = input.charCodeAt(index++);
+      character = input.charCodeAt(index++);
-      if (delimiter === char) break;
+      if (delimiter === character) break;
-      if (92 === char) { // \
+      if (92 === character) { // \
         string += input.slice(stringStart, index - 1) + readEscapeSequence();
         stringStart = index;
       }
       // EOF or `\n` terminates a string literal. If we haven't found the
       // ending delimiter by now, raise an exception.
-      else if (index >= length || isLineTerminator(char)) {
+      else if (index >= length || isLineTerminator(character)) {
         string += input.slice(stringStart, index - 1);
-        raise({}, errors.unfinishedString, string + String.fromCharCode(char));
+        raise({}, errors.unfinishedString, string + String.fromCharCode(character));
       }
     }
     string += input.slice(stringStart, index - 1);
@@ -638,10 +669,10 @@ define(function(require, exports, module) {
   // If a hexadecimal number is encountered, it will be converted.
 
   function scanNumericLiteral() {
-    var char = input.charAt(index)
+    var character = input.charAt(index)
       , next = input.charAt(index + 1);
 
-    var value = ('0' === char && ~'xX'.indexOf(next || null)) ?
+    var value = ('0' === character && 'xX'.indexOf(next || null) >= 0) ?
       readHexLiteral() : readDecLiteral();
 
     return {
@@ -693,11 +724,11 @@ define(function(require, exports, module) {
     }
 
     // Binary exponents are optional
-    if (~'pP'.indexOf(input.charAt(index) || null)) {
+    if ('pP'.indexOf(input.charAt(index) || null) >= 0) {
       index++;
 
       // Sign part is optional and defaults to 1 (positive).
-      if (~'+-'.indexOf(input.charAt(index) || null))
+      if ('+-'.indexOf(input.charAt(index) || null) >= 0)
         binarySign = ('+' === input.charAt(index++)) ? 1 : -1;
 
       exponentStart = index;
@@ -729,10 +760,10 @@ define(function(require, exports, module) {
       while (isDecDigit(input.charCodeAt(index))) index++;
     }
     // Exponent part is optional.
-    if (~'eE'.indexOf(input.charAt(index) || null)) {
+    if ('eE'.indexOf(input.charAt(index) || null) >= 0) {
       index++;
       // Sign part is optional.
-      if (~'+-'.indexOf(input.charAt(index) || null)) index++;
+      if ('+-'.indexOf(input.charAt(index) || null) >= 0) index++;
       // An exponent is required to contain at least one decimal digit.
       if (!isDecDigit(input.charCodeAt(index)))
         raise({}, errors.malformedNumber, input.slice(tokenStart, index));
@@ -754,7 +785,7 @@ define(function(require, exports, module) {
       case 'n': index++; return '\n';
       case 'r': index++; return '\r';
       case 't': index++; return '\t';
-      case 'v': index++; return '\v';
+      case 'v': index++; return '\x0B';
       case 'b': index++; return '\b';
       case 'f': index++; return '\f';
       // Skips the following span of white-space.
@@ -790,19 +821,16 @@ define(function(require, exports, module) {
     tokenStart = index;
     index += 2; // --
 
-    var char = input.charAt(index)
+    var character = input.charAt(index)
       , content = ''
       , isLong = false
       , commentStart = index;
 
-    if ('[' === char) {
+    if ('[' === character) {
       content = readLongString();
       // This wasn't a multiline comment after all.
-      if (false === content) content = char;
+      if (false === content) content = character;
-      else {
+      else isLong = true;
-        isLong = true;
-        index += 2; // Trailing --
-      }
     }
     // Scan until next line as long as it's not a multiline comment.
     if (!isLong) {
@@ -829,7 +857,7 @@ define(function(require, exports, module) {
     var level = 0
       , content = ''
       , terminator = false
-      , char, stringStart;
+      , character, stringStart;
 
     index++; // [
 
@@ -848,11 +876,11 @@ define(function(require, exports, module) {
 
     stringStart = index;
     while (index < length) {
-      char = input.charAt(index++);
+      character = input.charAt(index++);
 
       // We have to keep track of newlines as `skipWhiteSpace()` does not get
       // to scan this part.
-      if (isLineTerminator(char.charCodeAt(0))) {
+      if (isLineTerminator(character.charCodeAt(0))) {
         line++;
         lineStart = index;
       }
@@ -860,7 +888,7 @@ define(function(require, exports, module) {
       // Once the delimiter is found, iterate through the depth count and see
       // if it matches.
 
-      if (']' === char) {
+      if (']' === character) {
         terminator = true;
         for (var i = 0; i < level; i++) {
           if ('=' !== input.charAt(index + i)) terminator = false;
@@ -870,11 +898,6 @@ define(function(require, exports, module) {
 
       // We reached the end of the multiline string. Get out now.
       if (terminator) break;
-
-      if ('\\' === char) {
-        content += input.slice(stringStart, index - 1) + readEscapeSequence();
-        stringStart = index;
-      }
     }
     content += input.slice(stringStart, index - 1);
     index += level + 1;
@@ -905,16 +928,6 @@ define(function(require, exports, module) {
     return false;
   }
 
-  // Check if the given expression exists and raise an exception if not.
-  //
-  // As expressions can return null due to the design of the parser, we often
-  // need this strict expression check as well.
-
-  function expectExpression(expression) {
-    if (null == expression) raiseUnexpectedToken('<expression>', token);
-    else return expression;
-  }
-
   // Expect the next token value to match. If not, throw an exception.
 
   function expect(value) {
@@ -924,31 +937,31 @@ define(function(require, exports, module) {
 
   // ### Validation functions
 
-  function isWhiteSpace(char) {
+  function isWhiteSpace(character) {
-    return 9 === char || 32 === char || 0xB === char || 0xC === char;
+    return 9 === character || 32 === character || 0xB === character || 0xC === character;
   }
 
-  function isLineTerminator(char) {
+  function isLineTerminator(character) {
-    return 10 === char || 13 === char;
+    return 10 === character || 13 === character;
   }
 
-  function isDecDigit(char) {
+  function isDecDigit(character) {
-    return char >= 48 && char <= 57;
+    return character >= 48 && character <= 57;
   }
 
-  function isHexDigit(char) {
+  function isHexDigit(character) {
-    return (char >= 48 && char <= 57) || (char >= 97 && char <= 102) || (char >= 65 && char <= 70);
+    return (character >= 48 && character <= 57) || (character >= 97 && character <= 102) || (character >= 65 && character <= 70);
   }
 
   // From [Lua 5.2](http://www.lua.org/manual/5.2/manual.html#8.1) onwards
   // identifiers cannot use locale-dependet letters.
 
-  function isIdentifierStart(char) {
+  function isIdentifierStart(character) {
-    return (char >= 65 && char <= 90) || (char >= 97 && char <= 122) || 95 === char;
+    return (character >= 65 && character <= 90) || (character >= 97 && character <= 122) || 95 === character;
   }
 
-  function isIdentifierPart(char) {
+  function isIdentifierPart(character) {
-    return (char >= 65 && char <= 90) || (char >= 97 && char <= 122) || 95 === char || (char >= 48 && char <= 57);
+    return (character >= 65 && character <= 90) || (character >= 97 && character <= 122) || 95 === character || (character >= 48 && character <= 57);
   }
 
   // [3.1 Lexical Conventions](http://www.lua.org/manual/5.2/manual.html#3.1)
@@ -974,7 +987,7 @@ define(function(require, exports, module) {
   }
 
   function isUnary(token) {
-    if (Punctuator === token.type) return ~'#-'.indexOf(token.value);
+    if (Punctuator === token.type) return '#-'.indexOf(token.value) >= 0;
     if (Keyword === token.type) return 'not' === token.value;
     return false;
   }
@@ -1004,6 +1017,61 @@ define(function(require, exports, module) {
     }
   }
 
+  // Scope
+  // -----
+
+  // Store each block scope as a an array of identifier names. Each scope is
+  // stored in an FILO-array.
+  var scopes
+    // The current scope index
+    , scopeDepth
+    // A list of all global identifier nodes.
+    , globals
+    // A list of all global identifiers names used for faster lookup.
+    // @TODO benchmark, with exposing the globals this entire implementation
+    // should probably change.
+    , globalNames;
+
+  // Create a new scope inheriting all declarations from the previous scope.
+  function createScope() {
+    scopes.push(Array.apply(null, scopes[scopeDepth++]));
+  }
+
+  // Exit and remove the current scope.
+  function exitScope() {
+    scopes.pop();
+    scopeDepth--;
+  }
+
+  // Add identifier name to the current scope if it doesnt already exist.
+  function scopeIdentifierName(name) {
+    if (-1 !== indexOf.call(scopes[scopeDepth], name)) return;
+    scopes[scopeDepth].push(name);
+  }
+
+  // Add identifier to the current scope
+  function scopeIdentifier(node) {
+    scopeIdentifierName(node.name);
+    attachScope(node, true);
+  }
+
+  // Attach scope information to node. If the node is global, store it in the
+  // globals array so we can return the information to the user.
+  function attachScope(node, isLocal) {
+    if (!isLocal && -1 === indexOf.call(globalNames, node.name)) {
+      globalNames.push(node.name);
+      globals.push(node);
+    }
+
+    node.isLocal = isLocal;
+  }
+
+  // Is the identifier name available in this scope.
+  function scopeHasName(name) {
+    return (-1 !== indexOf.call(scopes[scopeDepth], name));
+  }
+
+
   // Parse functions
   // ---------------
 
@@ -1027,6 +1095,9 @@ define(function(require, exports, module) {
     var block = []
       , statement;
 
+    // Each block creates a new scope.
+    if (options.scope) createScope();
+
     while (!isBlockFollow(token)) {
       // Return has to be the last statement in a block.
       if ('return' === token.value) {
@@ -1038,6 +1109,8 @@ define(function(require, exports, module) {
       // ignore some statements, such as EmptyStatement.
       if (statement) block.push(statement);
     }
+
+    if (options.scope) exitScope();
     // Doesn't really need an ast node
     return block;
   }
@@ -1081,7 +1154,14 @@ define(function(require, exports, module) {
   //     label ::= '::' Name '::'
 
   function parseLabelStatement() {
-    var label = parseIdentifier();
+    var name = token.value
+      , label = parseIdentifier();
+
+    if (options.scope) {
+      scopeIdentifierName('::' + name + '::');
+      attachScope(label, true);
+    }
+
     expect('::');
     return ast.labelStatement(label);
   }
@@ -1095,7 +1175,10 @@ define(function(require, exports, module) {
   //     goto ::= 'goto' Name
 
   function parseGotoStatement() {
-    var label = parseIdentifier();
+    var name = token.value
+      , label = parseIdentifier();
+
+    if (options.scope) label.isLabel = scopeHasName('::' + name + '::');
     return ast.gotoStatement(label);
   }
 
@@ -1110,7 +1193,7 @@ define(function(require, exports, module) {
   //     while ::= 'while' exp 'do' block 'end'
 
   function parseWhileStatement() {
-    var condition = parseExpression();
+    var condition = parseExpectedExpression();
     expect('do');
     var body = parseBlock();
     expect('end');
@@ -1122,7 +1205,7 @@ define(function(require, exports, module) {
   function parseRepeatStatement() {
     var body = parseBlock();
     expect('until');
-    var condition = expectExpression(parseExpression());
+    var condition = parseExpectedExpression();
     return ast.repeatStatement(condition, body);
   }
 
@@ -1135,7 +1218,7 @@ define(function(require, exports, module) {
       var expression = parseExpression();
       if (null != expression) expressions.push(expression);
       while (consume(',')) {
-        expression = expectExpression(parseExpression());
+        expression = parseExpectedExpression();
         expressions.push(expression);
       }
       consume(';'); // grammar tells us ; is optional here.
@@ -1151,12 +1234,17 @@ define(function(require, exports, module) {
       , condition
       , body;
 
-    do {
+    condition = parseExpectedExpression();
-      condition = parseExpression();
+    expect('then');
+    body = parseBlock();
+    clauses.push(ast.ifClause(condition, body));
+
+    while (consume('elseif')) {
+      condition = parseExpectedExpression();
       expect('then');
       body = parseBlock();
       clauses.push(ast.elseifClause(condition, body));
-    } while (consume('elseif'));
+    }
 
     if (consume('else')) {
       body = parseBlock();
@@ -1178,16 +1266,19 @@ define(function(require, exports, module) {
     var variable = parseIdentifier()
       , body;
 
+    // The start-identifier is local.
+    if (options.scope) scopeIdentifier(variable);
+
     // If the first expression is followed by a `=` punctuator, this is a
     // Numeric For Statement.
     if (consume('=')) {
       // Start expression
-      var start = expectExpression(parseExpression());
+      var start = parseExpectedExpression();
       expect(',');
       // End expression
-      var end = expectExpression(parseExpression());
+      var end = parseExpectedExpression();
       // Optional step expression
-      var step = consume(',') ? expectExpression(parseExpression()) : null;
+      var step = consume(',') ? parseExpectedExpression() : null;
 
       expect('do');
       body = parseBlock();
@@ -1199,13 +1290,18 @@ define(function(require, exports, module) {
     } else {
       // The namelist can contain one or more identifiers.
       var variables = [variable];
-      while (consume(',')) variables.push(parseIdentifier());
+      while (consume(',')) {
+        variable = parseIdentifier();
+        // Each variable in the namelist is locally scoped.
+        if (options.scope) scopeIdentifier(variable);
+        variables.push(variable);
+      }
       expect('in');
       var iterators = [];
 
       // One or more expressions in the explist.
       do {
-        var expression = expectExpression(parseExpression());
+        var expression = parseExpectedExpression();
         iterators.push(expression);
       } while (consume(','));
 
@@ -1228,26 +1324,41 @@ define(function(require, exports, module) {
   //        | 'local' Name {',' Name} ['=' exp {',' exp}
 
   function parseLocalStatement() {
+    var name;
+
     if (Identifier === token.type) {
-      var variables = [];
+      var variables = []
-      var init = [];
+        , init = [];
 
       do {
-        variables.push(parseIdentifier());
+        name = parseIdentifier();
+
+        variables.push(name);
       } while (consume(','));
 
       if (consume('=')) {
         do {
-          var expression = expectExpression(parseExpression());
+          var expression = parseExpectedExpression();
           init.push(expression);
         } while (consume(','));
       }
 
+      // Declarations doesn't exist before the statement has been evaluated.
+      // Therefore assignments can't use their declarator. And the identifiers
+      // shouldn't be added to the scope until the statement is complete.
+      if (options.scope) {
+        for (var i = 0, l = variables.length; i < l; i++) {
+          scopeIdentifier(variables[i]);
+        }
+      }
+
       return ast.localStatement(variables, init);
     }
     if (consume('function')) {
+      name = parseIdentifier();
+      if (options.scope) scopeIdentifier(name);
+
       // MemberExpressions are not allowed in local function statements.
-      var name = parseIdentifier();
       return parseFunctionDeclaration(name, true);
     } else {
       raiseUnexpectedToken('<name>', token);
@@ -1268,18 +1379,19 @@ define(function(require, exports, module) {
       , expression = parsePrefixExpression();
 
     if (null == expression) return unexpected(token);
-    if (~',='.indexOf(token.value)) {
+    if (',='.indexOf(token.value) >= 0) {
       var variables = [expression]
         , init = []
         , exp;
 
       while (consume(',')) {
-        exp = expectExpression(parsePrefixExpression());
+        exp = parsePrefixExpression();
+        if (null == exp) raiseUnexpectedToken('<expression>', token);
         variables.push(exp);
       }
       expect('=');
       do {
-        exp = expectExpression(parseExpression());
+        exp = parseExpectedExpression();
         init.push(exp);
       } while (consume(','));
       return ast.assignmentStatement(variables, init);
@@ -1306,7 +1418,6 @@ define(function(require, exports, module) {
     return ast.identifier(identifier);
   }
 
-
   // Parse the functions parameters and body block. The name should already
   // have been parsed and passed to this declaration function. By separating
   // this we allow for anonymous functions in expressions.
@@ -1318,28 +1429,39 @@ define(function(require, exports, module) {
   //     parlist ::= Name {',' Name} | [',' '...'] | '...'
 
   function parseFunctionDeclaration(name, isLocal) {
-    var isVararg = false;
     var parameters = [];
     expect('(');
 
-    if (consume('...')) isVararg = true;
+    // The declaration has arguments
-    else if (Identifier === token.type) {
+    if (!consume(')')) {
-      do {
+      // Arguments are a comma separated list of identifiers, optionally ending
-        if (consume('...')) {
+      // with a vararg.
-          isVararg = true;
+      while (true) {
+        if (Identifier === token.type) {
+          var parameter = parseIdentifier();
+          // Function parameters are local.
+          if (options.scope) scopeIdentifier(parameter);
+
+          parameters.push(parameter);
+
+          if (consume(',')) continue;
+          else if (consume(')')) break;
+        // No arguments are allowed after a vararg.
+        } else if (VarargLiteral === token.type) {
+          parameters.push(parsePrimaryExpression());
+          expect(')');
           break;
+        } else {
+          raiseUnexpectedToken('<name> or \'...\'', token);
+        }
       }
-        parameters.push(parseIdentifier());
-      } while (consume(','));
     }
-    if (isVararg) expect(')');
-    else if (!consume(')')) raiseUnexpectedToken('<name> or \'...\'', token);
 
     var body = parseBlock();
     expect('end');
 
     isLocal = isLocal || false;
-    return ast.functionStatement(name, parameters, isVararg, isLocal, body);
+    return ast.functionStatement(name, parameters, isLocal, body);
   }
 
   // Parse the function name as identifiers and member expressions.
@@ -1347,14 +1469,20 @@ define(function(require, exports, module) {
   //     Name {'.' Name} [':' Name]
 
   function parseFunctionName() {
-    var base = parseIdentifier();
+    var base = parseIdentifier()
+      , name;
+    if (options.scope) attachScope(base, false);
 
     while (consume('.')) {
-      base = ast.memberExpression(base, '.', parseIdentifier());
+      name = parseIdentifier();
+      if (options.scope) attachScope(name, false);
+      base = ast.memberExpression(base, '.', name);
     }
 
     if (consume(':')) {
-      base = ast.memberExpression(base, ':', parseIdentifier());
+      name = parseIdentifier();
+      if (options.scope) attachScope(name, false);
+      base = ast.memberExpression(base, ':', name);
     }
 
     return base;
@@ -1372,15 +1500,15 @@ define(function(require, exports, module) {
 
     while (true) {
       if (Punctuator === token.type && consume('[')) {
-        key = parseExpression();
+        key = parseExpectedExpression();
         expect(']');
         expect('=');
-        value = expectExpression(parseExpression());
+        value = parseExpectedExpression();
         fields.push(ast.tableKey(key, value));
       } else if (Identifier === token.type) {
-        key = parseExpression();
+        key = parseExpectedExpression();
         if (consume('=')) {
-          value = parseExpression();
+          value = parseExpectedExpression();
           fields.push(ast.tableKeyString(key, value));
         } else {
           fields.push(ast.tableValue(key));
@@ -1389,7 +1517,7 @@ define(function(require, exports, module) {
         if (null == (value = parseExpression())) break;
         fields.push(ast.tableValue(value));
       }
-      if (~',;'.indexOf(token.value)) {
+      if (',;'.indexOf(token.value) >= 0) {
         next();
         continue;
       }
@@ -1402,7 +1530,8 @@ define(function(require, exports, module) {
   // Expression parser
   // -----------------
   //
-  // Expressions are evaluated and always return a value.
+  // Expressions are evaluated and always return a value. If nothing is
+  // matched null will be returned.
   //
   //     exp ::= (unop exp | primary | prefixexp ) { binop exp }
   //
@@ -1418,6 +1547,15 @@ define(function(require, exports, module) {
     return expression;
   }
 
+  // Parse an expression expecting it to be valid.
+
+  function parseExpectedExpression() {
+    var expression = parseExpression();
+    if (null == expression) raiseUnexpectedToken('<expression>', token);
+    else return expression;
+  }
+
+
   // Return the precedence priority of the operator.
   //
   // As unary `-` can't be distinguished from binary `-`, unary precedence
@@ -1427,23 +1565,23 @@ define(function(require, exports, module) {
   // the expensive CompareICStub which took ~8% of the parse time.
 
   function binaryPrecedence(operator) {
-    var char = operator.charCodeAt(0)
+    var character = operator.charCodeAt(0)
       , length = operator.length;
 
     if (1 === length) {
-      switch (char) {
+      switch (character) {
         case 94: return 10; // ^
         case 42: case 47: case 37: return 7; // * / %
         case 43: case 45: return 6; // + -
         case 60: case 62: return 3; // < >
       }
     } else if (2 === length) {
-      switch (char) {
+      switch (character) {
         case 46: return 5; // ..
         case 60: case 62: case 61: case 126: return 3; // <= >= == ~=
         case 111: return 1; // or
       }
-    } else if (97 === char && 'and' === operator) return 2;
+    } else if (97 === character && 'and' === operator) return 2;
     return 0;
   }
 
@@ -1464,7 +1602,8 @@ define(function(require, exports, module) {
     // UnaryExpression
     if (isUnary(token)) {
       next();
-      var argument = expectExpression(parseSubExpression(8));
+      var argument = parseSubExpression(8);
+      if (argument == null) raiseUnexpectedToken('<expression>', token);
       expression = ast.unaryExpression(operator, argument);
     }
     if (null == expression) {
@@ -1490,7 +1629,8 @@ define(function(require, exports, module) {
       // Right-hand precedence operators
       if ('^' === operator || '..' === operator) precedence--;
       next();
-      var right = expectExpression(parseSubExpression(precedence));
+      var right = parseSubExpression(precedence);
+      if (null == right) raiseUnexpectedToken('<expression>', token);
       expression = ast.binaryExpression(operator, expression, right);
     }
     return expression;
@@ -1503,14 +1643,20 @@ define(function(require, exports, module) {
   //     args ::= '(' [explist] ')' | tableconstructor | String
 
   function parsePrefixExpression() {
-    var base;
+    var base, name
+      // Keep track of the scope, if a parent is local so are the children.
+      , isLocal;
 
     // The prefix
     if (Identifier === token.type) {
+      name = token.value;
       base = parseIdentifier();
+      // Set the parent scope.
+      if (options.scope) attachScope(base, isLocal = scopeHasName(name));
     } else if (consume('(')) {
-      base = parseExpression();
+      base = parseExpectedExpression();
       expect(')');
+      if (options.scope) isLocal = base.isLocal;
     } else {
       return null;
     }
@@ -1518,23 +1664,25 @@ define(function(require, exports, module) {
     // The suffix
     var expression, identifier;
     while (true) {
-      expectExpression(base);
       if (Punctuator === token.type) {
         switch (token.value) {
           case '[':
             next();
-            expression = parseExpression();
+            expression = parseExpectedExpression();
             base = ast.indexExpression(base, expression);
             expect(']');
             break;
           case '.':
             next();
             identifier = parseIdentifier();
+            // Inherit the scope
+            if (options.scope) attachScope(identifier, isLocal);
             base = ast.memberExpression(base, '.', identifier);
             break;
           case ':':
             next();
             identifier = parseIdentifier();
+            if (options.scope) attachScope(identifier, isLocal);
             base = ast.memberExpression(base, ':', identifier);
             // Once a : is found, this has to be a callexpression, otherwise
             // throw an error.
@@ -1569,7 +1717,7 @@ define(function(require, exports, module) {
           var expression = parseExpression();
           if (null != expression) expressions.push(expression);
           while (consume(',')) {
-            expression = expectExpression(parseExpression());
+            expression = parseExpectedExpression();
             expressions.push(expression);
           }
 
@@ -1583,9 +1731,7 @@ define(function(require, exports, module) {
       }
 
     } else if (StringLiteral === token.type) {
-      var string = token.value;
+      return ast.stringCallExpression(base, parsePrimaryExpression());
-      next();
-      return ast.stringCallExpression(base, string);
     }
 
     raiseUnexpectedToken('function arguments', token);
@@ -1595,21 +1741,19 @@ define(function(require, exports, module) {
   //          | functiondef | tableconstructor | '...'
 
   function parsePrimaryExpression() {
-    var literals = StringLiteral | NumericLiteral | BooleanLiteral | NilLiteral
+    var literals = StringLiteral | NumericLiteral | BooleanLiteral | NilLiteral | VarargLiteral
-      , value = token.value;
+      , value = token.value
+      , type = token.type;
 
-    if (token.type & literals) {
+    if (type & literals) {
       var raw = input.slice(token.range[0], token.range[1]);
       next();
-      return ast.literal(value, raw);
+      return ast.literal(type, value, raw);
-    } else if (Keyword === token.type && 'function' === token.value) {
+    } else if (Keyword === type && 'function' === value) {
       next();
       return parseFunctionDeclaration(null);
-    } else if (Punctuator === token.type) {
+    } else if (consume('{'))
-      // Semantically dotsliteral can only exist within a vararg functions.
+      return parseTableConstructor();
-      if (consume('...')) return ast.varargLiteral(value);
-      if (consume('{')) return parseTableConstructor();
-    }
   }
 
   // Parser
@@ -1618,6 +1762,8 @@ define(function(require, exports, module) {
   // Export the main parser.
   //
   //   - `wait` Hold parsing until end() is called. Defaults to false
+  //   - `comments` Store comments. Defaults to true.
+  //   - `scope` Track identifier scope. Defaults to false.
   //
   // Example:
   //
@@ -1641,6 +1787,11 @@ define(function(require, exports, module) {
     line = 1;
     lineStart = 0;
     length = input.length;
+    // When tracking identifier scope, initialize with an empty scope.
+    scopes = [[]];
+    scopeDepth = 0;
+    globals = [];
+    globalNames = [];
 
     if (options.comments) comments = [];
     if (!options.wait) return end();
@@ -1668,6 +1819,7 @@ define(function(require, exports, module) {
 
     var chunk = parseChunk();
     if (options.comments) chunk.comments = comments;
+    if (options.scope) chunk.globals = globals;
     return chunk;
   }