Avoid regex balancing group to move out of parentheses

Question

I'm using the following regex to match the contents of any datascript script referencing a specific UDF:

\[?shared3\]?\.\[?stringsum\]?(((?'Open'\()[^()]*)+((?'Close-Open'\))[^()]*)+)*

it matches any instance of:

Shared3.StringSum(<some contents here>)

Using the balancing groups, I'm trying to also support cases like:

Shared3.StringSum(SomeOtherMethod('input') + AnotherMethod('input'))

However, I'm running into trouble, when the input is like:

Shared3.StringSum(SomeOtherMethod('input') + AnotherMethod('input')) + ThirdMethod('input')

In the last case, my regex also matches the ThirdMethod('input') part.

Is there any way I can alter my regex, so it stops matching as soon as the "parentheses count" is 0?

Try `\[?shared3]?\.\[?stringsum]?\(((?>[^()]+|(?'Open'\()|(?'Close-Open'\)))*)\)`, see [demo](http://regexstorm.net/tester?p=%5c%5b%3fshared3%5d%3f%5c.%5c%5b%3fstringsum%5d%3f%5c%28%28%28%3f%3e%5b%5e%28%29%5d%2b%7c%28%3f%27Open%27%5c%28%29%7c%28%3f%27Close-Open%27%5c%29%29%29*%29%5c%29&i=Shared3.StringSum%28SomeOtherMethod%28%27input1%27%29+%2b+AnotherMethod%28%27input2%27%29%29%0d%0aShared3.StringSum%28SomeOtherMethod%28%27input1%27%29+%2b+AnotherMethod%28%27input2%27%29%29+%2b+ThirdMethod%28%27input%27%29&o=i). — Wiktor Stribiżew, Apr 20 '20 at 14:27
Great, this fixes the issue. It isn't the exact regex I need, because of some other issues, but I was able to solve them. — PaulVrugt, Apr 20 '20 at 14:51
What other issues? If it fixes the current issue it is a valid solution. Please edit the question if you want me to adjust it. — Wiktor Stribiżew, Apr 20 '20 at 14:55
These other issues are unrelated to the question scope, so your answer is correct. No reason to panic :) Thank you! — PaulVrugt, Apr 20 '20 at 15:01

score 3 · Accepted Answer · edited Apr 22 '20 at 14:19

You may use

\[?shared3]?\.\[?stringsum]?\(((?>[^()]+|(?'Open'\()|(?'Close-Open'\)))*)\)

Details

\[?shared3]? - an optional [, shared, and an optional ]
\. - a dot
\[?stringsum]? - an optional[,stringsum, and an optional]`
\( - a (
((?>[^()]+|(?'Open'\()|(?'Close-Open'\)))*) - Group 1: one or more occurrences of
- [^()]+| - 1+ chars other than ( and ), or
- (?'Open'\()| - Group "Open": pushes ( into group stack
- (?'Close-Open'\)) - Group "Close" and "Open": pops the ) from the Open group stack and saves the current level substring into Close group
\) - a ) char to finish things up

1 Answers1