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From: jgreely@oz.cis.ohio-state.edu (J Greely)
Newsgroups: comp.lang.perl
Subject: Re: Novice Question, Successive Lines
Message-ID: <JGREELY.90Mar21054359@oz.cis.ohio-state.edu>
Date: 21 Mar 90 10:43:59 GMT
References: <13447@cgl.ucsf.EDU>
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In-reply-to: alonso@maxwell.mmwb.ucsf.edu's message of 21 Mar 90 04:55:20 GMT

In article <13447@cgl.ucsf.EDU> alonso@maxwell.mmwb.ucsf.edu
 (Darwin Alonso) writes:
>How would one get perl to replace two or more successive blank lines 
>with one blank line?

Whole bunch of possibilities.  Here's a relatively straightforward
approach:

while (<>) {
	if (/^$/) {
		$seen++;
	}else{
		print "\n" if $seen;
		$seen = 0;
		print;
	}
}
print "\n" if $seen;


A shorter solution that chews up more memory:
undef $/;
$_ = <>;
s/\n{3,}/\n\n/g;
s/^\n{2,}/\n/;
print;


I can't think of a better solution (shorter and more twisted, natch)
at the moment, but I'm sure one of the other fertile minds out there
can.
--
J Greely (jgreely@cis.ohio-state.edu; osu-cis!jgreely)