sub print_power_of_2 {
    my $x = shift;
    my $power_of_2 = sub { return $x ** 2; };
    my $result = $power_of_2->();
    print "$x^2 = $result\n";
}

[download]
Note that named subroutine declarations are always evaluated before any code that call them, so the location is "irrelevant", which also means that there aren't any situations where you "must keep the location" of the declaration.

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re: nested routines, anonymous routines and location dependency by Joost
in thread nested routines, anonymous routines and location dependency 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.