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Re^2: multiple occurences when using Parse::RecDescent

by graff (Chancellor)
on Mar 30, 2005 at 09:45 UTC ( [id://443389] : note . print w/replies, xml ) Need Help??

in reply to Re: multiple occurences when using Parse::RecDescent
in thread multiple occurences when using Parse::RecDescent

For some reason, I couldn't get your rule to handle repeated ocurrences of the target pattern. Here's a variation that worked for me (and it includes printing out the "text" that it finds, to prove the result):
startrule: statement(s) statement: print open text end print: /\s*print\s*/ open: "'" text: /([^']*)/ {print " $item[1] "} end: "'"
Generally, for a grammar that's supposed to handle one or more of a basic top-level unit, it's easier/clearer to assign a name to that unit and have just that, plus "(s)", as the startrule, then break it down into components in a later rule.

UPDATE: The OP said: i need it so that it will allow this several times down the textarea and spot an error in any of the occurences.

To make it work that way, the startrule should be:

startrule: statement(s) /$/
which says that after matching one or more patterns that satisfy "statement", the parser should find the end-of-string. Without this, any string that starts with a valid statement will be accepted, regardless of any unmatchable content that follows.