Javascript grammar

Hi,
I downloaded and inspected the Ecmascript-262 grammar on page 157:


http://www.ecma-international.org/publications/standards/Ecma-262.htm
http://www.ecma-international.org/publications/files/ecma-st/ECMA-262.pdf


I found a reduce-reduce conflict in that the kernels for "FunctionExpression"
and "FunctionDeclaration" both start from the same LALR state (state 0), and
can consist of an identical sequence of symbols:


FunctionDeclaration ->
                'function' '<Identifier>' '(' FormalParameterList_opt ')' '{' FunctionBody '}'


FunctionExpression ->
                'function' '<Identifier_opt>' '(' FormalParameterList_opt ')' '{' FunctionBody '}'


and have these lookaheads in common: ++ -- ; [ ( + -


(I think my tool is correct from manually looking through the grammar)


Is it an accepted way of tolerating a reduce-reduce conflict by detecting
unsuitable reductions in the symantic analysis?




The list of relevant productions are:




************************************************************************************


Program ->
                SourceElements


SourceElements ->
                SourceElement |
                SourceElements SourceElement


SourceElement ->
                Statement |
                FunctionDeclaration


FunctionDeclaration ->
                'function' '<Identifier>' '(' FormalParameterList_opt ')' '{' FunctionBody '}'


Statement ->
                  Block |
                  VariableStatement |
                  EmptyStatement |
                  ExpressionStatement |
                  IfStatement |
                  IterationStatement |
                  ContinueStatement |
                  BreakStatement |
                  ReturnStatement |
                  WithStatement |
                  LabelledStatement |
                  SwitchStatement |
                  ThrowStatement |
                  TryStatement


ExpressionStatement ->
                  Expression ';'


Expression ->
                AssignmentExpression |
                Expression ',' AssignmentExpression


AssignmentExpression ->
                ConditionalExpression |
                LeftHandSideExpression '<AssignmentOperator>' AssignmentExpression


LeftHandSideExpression ->
                NewExpression |
                CallExpression


NewExpression ->
                MemberExpression |
                'new' NewExpression


MemberExpression ->
                PrimaryExpression |
                FunctionExpression |
                MemberExpression '[' Expression ']' |
                MemberExpression '.' '<Identifier>' |
                'new' MemberExpression Arguments


FunctionExpression ->
                'function' '<Identifier_opt>' '(' FormalParameterList_opt ')' '{' FunctionBody '}'

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