Adding to what others have said, it might be easier to get your head around this concept if you think of arrays and hashes as both being fancy kinds of lists. You can assign one to the other and maintain the same information (unlike assigning a list to a scalar, which only gives you the length of the list).

@a = ( 1, 2, 3, 4 );
%h = @a;
print $h{1}; # prints 2
print $h{3}; # prints 4
print $h{2}; # prints nothing (undefined hash element)

@b = %h;
print $b[2]; # Unknown, since the hash doesn't maintain order
             # Exact behavior is undefined, and often 
             # changes between perl versions.

$ref = { @a }; # $ref gets a hash ref, but the anonoymous ref
               # is built with an array.

[download]

"There is no shame in being self-taught, only in not trying to learn in the first place." -- Atrus, Myst: The Book of D'ni.

In reply to Re^3: wantarray - surprise behaviour by hardburn
in thread wantarray - surprise behaviour by shemp

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.