consider a recursive solution:
my @flattened_array = flatten($nested_array_ref); sub flatten { my $array = shift; my @results = (); foreach my $element ( @$array ) { if( ref $element eq 'ARRAY' ) { push @results, flatten($element); } elsif( $element ) { push @results, $element; } } return @results; }

update: I investigated per rob_au's concerns with the following code using the above subroutine:

use Data::Dumper; use strict; my $nested_array_ref = [ '', [ 'a', [ 'b', 'c' ], '', 'd' ], 'value' ]; my @flattened_array = flatten($nested_array_ref); print Dumper(\@flattened_array);

and my output was this:

$VAR1 = [ 'a', 'b', 'c', 'd', 'value' ];

the example i gave explicitly passed an array_ref into the function to begin with, and @results is local to the subroutine, and does not get blown away during recursion.


In reply to Re: How to flatten an x-dimensional array? by AidanLee
in thread How to flatten an x-dimensional array? by Incognito

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.