I'm just saying that I've run into cases where 
for (split /\n/, $longstring) {
  ...
}

[download]

ran faster than 

open my $fh, '<', \$longstring;
while (<$fh>) {
  ....
}

[download]

In a perfect world, they would run the same speed (or at least really close). The second one is preferred any time there's a case that you want to run it on a huge file and don't want to load $longstring all into memory at once. The second code solves both cases, but if a majority of your cases are to have it already loaded in memory, then maybe you want to write it the first way for performance.

(If I made a top-level post out of this I'd want to do all the benchmarks and different perl versions, and I'd end up researching the Perl source code and all that, which I don't have time for right now)

In reply to Re^4: RE on lines read from in-memory scalar is very slow by NERDVANA
in thread RE on lines read from in-memory scalar is very slow by Danny

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.