ZlR:

I sometimes use this trick: Rather than reference the top hash everywhere, I create a reference to the "current" hash in each level of the loop, like so: 

#!/usr/bin/perl -w
use strict;
use warnings;

my %rez = (
    'host1' => {
        'tgt' => {
            'target_0011' => {
                '11C3' => '0C5C',
                '11E3' => '0C7C'
            },
        },
        'wwn' => [ 'foobar' ]
    },
);

for my $curHost (keys %rez) {
    my $host = $rez{$curHost}; # Use $$host{key} at this level

    print "HOST: $curHost\n";

    for my $curDev (keys %{$$host{tgt}}) {
        my $dev = $$host{tgt}{$curDev}; # Use $$dev{key} at this level

        # without using trick:
        my $bar = $rez{$curHost}{tgt}{$curDev}{'11E3'};

        # with trick:
        my $foo = $$dev{'11C3'};

        print "    DEV $curDev contains: ", join(", ", sort keys %$dev
+), "\n";
    }
}

[download]

This way, your references aren't a foot and a half long. You can easily add or remove a level of your structure pretty easily, too, since you needn't edit a bazillion lines of code--only the ones where you change levels. I normally use this trick when (a) I suspect that I'll have to rearrange the structure or (b) my references get too long.

...roboticus

In reply to Re: A better way for walking through HoHoH ? by roboticus
in thread A better way for walking through HoHoH ? by ZlR

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.