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Struggeling with RegExp - Experts needed.

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thomas:
Neither of your proposals is good, unluckily.

Joat's proposal will grab the right string, but it misses the point because it will not work with anything that is not quoted.
Dmoore's proposal does not work because variables cannot be expanded first (without some nasty hack), as that would replace $relative with an empty string and leave the brackets untouched.

The problem is so complicated because the regex is greedy. According to the documentation, you can use +? for a non-greedy match, so \(.+?\) would be the right thing. However, I tried that and it  did not compile...

dmoore:

--- Quote from: thomas on November 29, 2006, 12:43:01 am ---Dmoore's proposal does not work because variables cannot be expanded first (without some nasty hack), as that would replace $relative with an empty string and leave the brackets untouched.

--- End quote ---

I didn't claim a nasty hack wouldn't be required, but that's what happens when you try to be too cute with macro syntax :) (don't get me wrong, I like cute). I guess I am not sure how general these absolute/relative functions need to be. For instance, should this work:

(1) $relative($(LIBNAME($LIBTYPE)))

or only this:

(2) $relative($(LIBNAME))

and this

(3) $relative($LIBNAME)

(there's also the % syntax to worry about, or was that removed?)

if all of (1), (2) and (3) are required then you can see why I proposed what I did (because (1) wouldn't make any sense until all other substitutions had been made), albeit with the side effect that you would need to avoid substitution of "$relative" or "$absolute". If only (2) and (3) are required then you could capture what you need with:


--- Code: ---([^$]|^)(\$(absolute|relative)\((\$\([^\(\)]+\)|[^\(\)]+)\))

--- End code ---

(you may also want to allow for whitespace in the brackets with a few " *" scattered about)

PS: I'm not sure how non-greedy search would help in this case. Isn't the problem that the regex isn't greedy enough when there are sub-braces?

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