use strict;
use warnings;



local $/ = "\n##"; #record separator

while (<DATA>) {
    chomp;

    #print "\n<<<$_>>>\n"; # check input

    my ($head,$rest) = /^ (.*?) \n (.*) $/xs;

    # print record only if $rest contains alphanumerics
    print "##$_" if $rest =~ /\w/;
}




__DATA__
## This gets stripped



## This doesn't

Because it contains this line



## More headers

blah blah


## This should not get stripped, but it does



### This should prevent it from getting stripped, but it doesn't

stuff



#### This should also not get stripped



##### But it does

[download]

C:/Perl_524/bin\perl.exe -w d:/exp/pm_headers.pl 
## This doesn't

Because it contains this line


## More headers

blah blah

### This should prevent it from getting stripped, but it doesn't

stuff



Compilation finished at Wed Jul 22 17:59:57

[download]

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

In reply to Re: Tricky regex problem by LanX
in thread Tricky regex problem by nysus

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