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On Mon, 2008-08-04 at 09:52 -0700, rkevinburton@charter.net wrote:
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If I left factor the grammar I essentially have
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Thsi is not left factored, you have just left factored the first bit of it.
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classSourceElement
: classField
| classMethod
| classProperty
classCommon
: (s=STATIC)? (modifier=(PUBLIC|PRIVATE))?
classField
: c=classCommon VAR name=Identifier
-> ^( CFIELD $c $name )
| c=classCommon VAR name=Identifier COLON type=Identifier
-> ^( CFIELD $c $name TYPES $type)
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both of htese have a common prefix classCommon VAR Identifier, left factor these.
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classMethod
: c=classCommon name=Identifier formalParameterList functionBody
-> ^( $c formalParameterList functionBody )
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And so does this, <BR>
<BR>
You want to take all the classCommon stuff and start classSourceElement with it, then you have classField as:<BR>
<BR>
VAR name=Identifier <BR>
( COLON type=Identifier ->^(CFIELD $name TYPES $type)<BR>
| ->^(CFIELD $name)<BR>
)<BR>
<BR>
your classSourceElement the is:<BR>
<BR>
classSourceElement<BR>
: c=classCommon<BR>
( c1=classField<BR>
| c2=classProperty<BR>
etc.<BR>
<BR>
and you rewrite as ^(TYPEDECL $c $c1? $c2? etc).<BR>
<BR>
You AST walker can then semantically check whether static and so on are valid for this declaration.<BR>
Jim
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