Regex parameter parsing - regex

Question

I need to parse a file that includes function calls. For example:
function(otherFunction1(parameters1), otherFunction2(parameters2))
I need the output to be:
otherFunction1(parameters1), otherFunction2(parameters2)
My attempt is this:
open(my $DATA, '<', 'txt') or die "...";
while(my $line = <$DATA>){
$line =~ /\((\w+)\)/;
my $parameters = $1;
print "$parameters\n";
}
I am just getting
parameters1
Is there a way to use regexp to perhaps find the first and last occurrence of the specified character?
Thanks!

Answer 1

You'll need a recursive regex to do it properly. Like this one (with the x flag):
(?(DEFINE)
(?<fn> # a function is:
\w+ \s* # a name
\( (?&paramList) \) # and a parameter list
)
(?<paramList>
(?:
\s* (?&param)
(?: , \s* (?&param) )* \s*
)*
)
(?<param> # a parameter is:
(?&fn) # a function call
| \w+ # or a simple value
)
)
\w+ \s* \( (?<extractedParameters>(?&paramList)) \)
Demo.
This is required to match the opening and closing parentheses. Just expand the syntax as needed.
The pattern at the bottom is equivalent to (?&fn) except it encloses the parameter list in a capture group.

Answer 2

You almost have it. You do want everything between the first and the last parentheses on each line, right? Unless the lines to parse are more complex than your example, this small change in code might be all you need.
$line =~ /\((.*)\)/;
my $parameters = $1;
Your \w+ will stop matching at the first non-word character in the string. In your example, that is the first right-hand parenthesis.