Using the simplest op that gets the job done is always good advice, both for speed and readability.

But for those that are addicted to regexes, the above situation won't bite speed too hard. The regex engine optimizes a fixed string to a Boyer Moore match, which is a tad slower than string equality: 

use Benchmark qw(:all) ;

my $value = 'FALSE';
my $count = 10_000_000;

cmpthese($count, {
                  'regex' => sub { $value =~ /^true$/i },
                  'eq'    => sub { lc $value eq "true" },
                 });

[download]
yields 
Benchmark: timing 10000000 iterations of eq, regex...

1048% perl boyer.pl
Benchmark: timing 10000000 iterations of eq, regex...
        eq:  9 wallclock secs ( 8.98 usr +  0.00 sys =  8.98 CPU) @ 11
+13585.75/s (n=10000000)
     regex: 16 wallclock secs (16.31 usr +  0.00 sys = 16.31 CPU) @ 61
+3120.78/s (n=10000000)
           Rate regex    eq
regex  613121/s    --  -45%
eq    1113586/s   82%    --

[download]
Unless that match is inside a tight loop, program performance will not be too degraded,

-Mark

In reply to Re: You don't always have to use regexes by kvale
in thread You don't always have to use regexes by petdance

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.