Help for this page

Select Code to Download


  1. or download this
    >perl -wMstrict -le
"my $s = 'x(y) (a(b)) ()() q (a(b)c()(d(e(f)g))h) q';
...

final regex:
(?^msx: ((?^msx: \( ([^()]* | (??{ our $rx }))* \) )) [^()]* ((?^msx: 
+\( ([^()]* | (??{ our $rx }))* \) )) )
  2. or download this
    
counted capture groups:
...
(?^msx: ((?^msx: \( ([^()]* | (??{ our $rx }))* \) )) [^()]* ((?^msx: 
+\( ([^()]* | (??{ our $rx }))* \) )) )
        |           |                        |      |        |        
+   |                        |      |
        1st begin   2nd begin                2-end  1st end  3rd begin
+   4th begin                4-end  3rd end