Re^2: regex extraction for variable number of args

Thank you - this is beautiful, elegant, simple and operational.

I modified it slightly to remove what I thought was unnecessary grouping - this still works:

qr{ 
    \&?          # Leading char for Sub-name -
   ( [^(),\s]+ ) # Sub-name OR arg
    [(,)]?       # Trailing "(" or comma
 }x;
[download]

Thanks also to others who posted working solutions.

As a learning experience, I would also like to understand why the repetition attempt in my O.P - the one without the /g - did not work. Any assistance on that ?

I hope life isn't a big joke, because I don't get it.
-SNL

Comment on Re^2: regex extraction for variable number of args Download Code

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Re^3: regex extraction for variable number of args by Corion (Patriarch) on Jul 21, 2012 at 14:24 UTC
A regular expression without /g will always match a string from the start, and only once. You need /g for making the engine try multiple times. Your for loop only gets one result. Whether that result is the first target or the last target hinges on where your regex can match.	[reply]
Re^4: regex extraction for variable number of args by NetWallah (Canon) on Jul 21, 2012 at 14:46 UTC
Ok - it is beginning to sink in - so - it appears that there is no useful/meaningful way to combine non-capturing parens and repetition, unless your pattern starts at the beginning - in which case, you are better-off with the "/g" modifier . Or you are always better-off with the "/g" modifier. So - is there a use case for non-capturing parens with repetition ? I hope life isn't a big joke, because I don't get it. -SNL	[reply]
Re^5: regex extraction for variable number of args by Corion (Patriarch) on Jul 22, 2012 at 07:15 UTC
I can think of many uses for non-capturing parentheses with repetition. In fact, non-capturing parentheses with repetition are more sane than capturing parentheses with repetition, because the capturing parentheses will only keep the last match of the repetition. As an example a simple checker to check that a line matches a CSV-like format, using non-capturing parentheses and repetition: `$line =~ /^(?:[^,]+\|"[^"]+")(?:,(?:[^,]+\|"[^"]+"))*$/` [download] That one matches one well-formed column, and then optionally a repetition of comma and more well-formed column.	[reply] [d/l]