http://www.perlmonks.org?node_id=832720


in reply to Regex: how to consider an unknown number of tabs?

Consider this checking out the $/ - input record separator in perlvar. 
#!/usr/bin/perl

use strict;

local $/ = "\n\n";

while (<DATA>) {
    print if ( ! /^r145/ );
}

__DATA__
c114: 0245, 0456, 1545
    2555, 2444, 0344
    0444, 3434, 1434

r145: 0544, 0688, 2988
    1332, 0221, 0867
    0655, 4548, 7463

c12: 2322, 0556, 3998
    3545, 2002, 4500
    5650, 0830, 3324
    3433, 7070, 3404

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