[Israel.pm] recursive regex

[Yossi.Itzkovich at ecitele.com]

Shlomo,

It works great !
But if I understand it correctly  it scans the data M+1 times (M=macro).
It is not a problem in my case, just of curiosity.

Yossi



                                                                                                                                   
                      Shlomo Yona                                                                                                  
                      <shlomo at cs.haifa         To:      Perl in Israel <perl at perl.org.il>                                          
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                      06/09/2004 12:24                                                                                             
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Hello.

Is this what you have in mind?

while(<DATA>) {
        print_begin_end_macro($1) if /BEGIN_(\S+)/;
}

sub print_begin_end_macro {
        my ($what)=@_;
        while(<DATA>) {
                if (/END_$what/) {
                        print qq{BEGIN_$what\tEND_$what\n} if /END_$what/;
                        return;
                }
                print_begin_end_macro($1) if /BEGIN_(\S+)/;
        }

}