Nice catch...it looks like I need to mention the semicolon (which may be supplied by automatic semicolon insertion).
The parentheses form is not intended to be a directive. allen >-----Original Message----- >From: [email protected] [mailto:es-discuss- >[email protected]] On Behalf Of Mike Samuel >Sent: Monday, September 21, 2009 6:33 PM >To: [email protected] >Subject: Use subset directive grammar > >From section 14.1 of >http://wiki.ecmascript.org/lib/exe/fetch.php?id=es3.1%3Aes3.1_proposal_w >orking_draft&cache=cache&media=es3.1:es5-tc392008-040.pdf > > A Directive Prologue is a sequence of zero or more >ExpressionStatement productions, > each of which having an Expression consists entirely of a >StringLiteral, that occur as the initial > SourceElement productions of a Program or FunctionBody. > >What does "consists entirely" mean? > >From the grammar in the appendix, to get from ExpressionStatement to >StringLiteral, I have to go through the following grammar chain: > ExpressionStatement -> AssignmentExpression -> >ConditionalExpression -> (lots of operator precedence elided) > -> LeftHandSideExpression -> NewExpression -> MemberExpression -> >PrimaryExpression -> Literal -> StringLiteral > >One way to define "consists entirely" might be: an A that consists >entirely of B if it matches A and B and all tokens were consumed by >matching B. >That definition is consistent with > "use strict" >but not > "use strict"; >since the ";" is actually part of the ExpressionStatement production. > >Is there a definition of "consists entirely" that matches > "use strict"; >and > "use strict" >but not > ("use strict"); >? > >Or can the last be part of a directive prologue? >_______________________________________________ >es-discuss mailing list >[email protected] >https://mail.mozilla.org/listinfo/es-discuss _______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
