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How do I split a file into an array using blank lines as delimiter

( #47236=categorized question: print w/ replies, xml ) Need Help??
Contributed by aaAzhyd on Dec 18, 2000 at 22:33 UTC
Q&A  > files


Description:

I have a file such as:

--
blah blah blah
blah blahblahblalh

oh yeah interesteing

no no no
nonnono

yes yes
--

I am wanting to read the file into an array spliting each element
by a blank line, such as @array[0] would be:

blah blah blah
blah blahblahblalh

Here is what I have tried doing:

open (LOG,"Messages.log"); while (<LOG>){ $string .= $_; } @array = split(/^\s*$/, $string);
and i have tried messing around with the regular expresion with no luck ..

Answer: Spliting a file into an array using blank lines as delimiter
contributed by davorg

The secret is to change $/ to the empty string. This will put Perl into 'paragraph mode', where the input record separator is one or more blank lines. Something like this:

#!/usr/bin/perl -w use strict; my @array; { local $/ = ''; @array = <DATA>; } print $array[0]; __END__ blah blah blah blah blahblahblalh oh yeah interesteing no no no nonnono yes yes
Answer: Spliting a file into an array using blank lines as delimiter
contributed by dsb

your code would work but the pattern you have '$string' splitting on is no good. Right now you have it matching any line with 0 or more whitespaces at the beginning. That's every line. Try this:

open (LOG,"Messages.log"); while (<LOG>){ $string .= $_; } @array = split(/\n{2,}/, $string); # note the new pattern

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