>>>>> "SC" == Simon Cozens <[EMAIL PROTECTED]> writes:
SC> rule comm_eol { <sp*> <comment>? <sp*> \n };
>>
>> aren't those <sp*>'s redundant? the first is overlapping with the one at
>> the beginning of comment.
SC> But <comment> only matches if there *is* a comment, and there may not
SC> be, so I want to match optional space at the EOL anyway.
ok, but since comment is optional, if it doesn't match, the two <sp>*
are back to back. is that needed? i just see too many <sp>* and that
could lead to backtracking issues (something i recall from MRE1).
SC> rule raiddev { <comment>*
>> i think that should be comm_eol as you want to skip all full comment lines.
SC> I thought the .* (or \N*) would skip the whole line. comm_eol just means
SC> "comment at end of line".
i figured that was what it meant. but . matches any char now so .* will
eat all the text until it is forced to backtrack. so \N* will stop at
the newline which is what i think you want in comm_eol.
>> that is how i understand it. the grammar automatically build a tree of
>> the grabs with hash keys being the rule names and multiples (rules with
>> quantifiers) being arrays.
SC> Great.
actually i just had another thought. you don't need any of the $foo :=
stuff as the match tree will have it all for you. unless you need a
single var having some grabbed stuff, you might as well let the match
object hold it all. you do want a tree from this parser so the single
vars will do no good. unless they also put stuff into the tree based on
their names. also if you use a scalar to grab something which is in a
quantified outer rule what is put in the var? a ref to a list of the
grabbed things?
uri
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Uri Guttman ------ [EMAIL PROTECTED] -------- http://www.stemsystems.com
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