This is a good situation for using a Schwartzian Transform. The code you have is close to right, but it's confusing and hard to follow a bit, partly because of all that logic in the sort block that isn't really part of the sorting. I'd move the regex matching out to a preliminary map, put just the sorting code in the sort block, and then map back to the part you want in the upper map... 

my @sortedkeys = map {
  $$_[0]
} sort {
  $$a[1] <=> $$b[1]
} map {
  $$etcpw{$_} =~ /[:](\d+)/;
  [$_, $1]
} keys %$etcpw;

[download]

Much easier to follow, if you ask me. As far as why your original code doesn't work, I think it's because pattern matches don't do the same thing in scalar context as they do in array context.

"In adjectives, with the addition of inflectional endings, a changeable long vowel (Qamets or Tsere) in an open, propretonic syllable will reduce to Vocal Shewa. This type of change occurs when the open, pretonic syllable of the masculine singular adjective becomes propretonic with the addition of inflectional endings."  — Pratico & Van Pelt, BBHG, p68

In reply to Re: Hash sorting (by value) woes by jonadab
in thread Hash sorting (by value) woes by sschneid

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.