Re: [Java Spec Report] JSR 201 enhanced-for comments

In trying to implement this, I found a HUGE problem - the proposed grammar is 
not LALR(1).  Remember how JSR 41 (assert statement) changed its grammar long 
after the public draft closed, because the proposed grammar was not LALR(1)?

>   /EnhancedForStatement:/
>        for ( /FormalParameter/ : /Expression/ )
>            /Statement/

When the parser sees "for (@A final int i", your proposal makes it impossible 
to decide whether you are starting a FormalParameter or 
LocalVariableDeclaration (as part of ForInitopt).  You are going to have to 
factor this statement out; I haven't yet had time to tackle the problem, but 
if I can find a factorization that works, I will post it.

You also need to add:
EnhancedForStatementNoShortIf:
   'for' '(' <whatever factorization works> ':' Expression ')'
       StatementNoShortIf

And you should explicitly list:
Statement:
   <all existing productions>
   EnhancedForStatement
StatementNoShortIf:
   <all existing productions>
   EnhancedForStatementNoShortIf:

-- 
Someday, I might put a cute statement here.

Eric Blake             [email protected]



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