Your brain is still doing C, C++, Java, whatever you used to do before perl.

While C style for loops do work in Perl, it's better to think of loops in terms of lists, arrays, sets:

for my $i ( 0..2 ) {
    for my $j ( 0..2 ) {
        ...
    }
}

[download]

But why do you have these hashes named $a{0}, $a{1}, $a{2}? Those sound like arrays, not hashes. In fact, I kept accidentally using square brackets instead of curlies, and then had to repair them.

Better yet, why not start thinking in meaningful terms, for example %expense, %income, %profits over the keys qw( January February March .... ). Hmmm ... still sounds like arrays.

What are you really trrying to achieve? As opposed to how you think you need to implement it ...?

--
TTTATCGGTCGTTATATAGATGTTTGCA

In reply to Re: Interpolating an array element as a hash name. by TomDLux
in thread Interpolating an array element as a hash name. by yam

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.