my @c = combine(5,@n); # get array of arrays
my @A = @$c[0];        # get first sub-array

[download]

Because the 'precedence' (if that's the proper term here) of the  @ array dereference sigil is so high, the expression  @$c[0] attempts to dereference an array reference held in the  $c scalar (not in the  @c array) and then access the element at index 0 in the referenced array. (Update: Actually, my first thought was that  @$c[0] would look like a 'degenerate' array slice, like @x[0]; not sure why the appropriate warning was not generated.) The expression  @{ $c[0] } is what is needed in the given example. 

>perl -wMstrict -MData::Dump -le
"my @c = (['x', 'y'], ['a', 'b'], ['c', 'd']);
 my $c = ['foo', 'bar'];
 ;;
 my @A1 = @  $c[0]  ;
 my @A2 = @{ $c[0] };
 dd \@A1;
 dd \@A2;
"
["foo"]

["x", "y"]

[download]

In reply to Re^7: Perl list items by AnomalousMonk
in thread Perl list items by robertw

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.