I think the reason I used the flip flop was so the subroutine held state as the OP was asking for a subroutine to provide this behaviour when being passed one line at a time (and because it was a bit fun). Your method does look faster for large files (and probably any size files) but I think you are cheeting a bit by using execution flow to hold state.

I propose a less interesting subroutine that is probably as fast as yours. Once $flipped is set there is only one check made in each sub call due to short circuiting the rest of the or when the first side is true.

#!/usr/local/bin/perl -w use strict; my $flipped=0; sub logit { my $line=shift; $line=~s/\0//g; return unless ($flipped or ($line=~/\S/ and ++$flipped)); print $line; } while (<DATA>) {&logit ($_)} __DATA__ we dont really need this again but here it is anyway

Cheers,
R.


In reply to Re^3: blank lines up to a point by Random_Walk
in thread blank lines up to a point by Anonymous Monk

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":



  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.