I'd use:

$HoA{$key} = \@fields;

[download]

unless I really wanted to copy the elements in @fields. Most often I'd do that sort of thing in a loop where @fields is local to the loop and the assignment is performed at the end of the loop block.

The trap with either of variants you show is that only a shallow copy is made. If @fields contains nested elements then the references are copied, not the nested data. Using \@fields makes it just a little clearer (at least to me) in that case that danger lurks under the surface because it is clearer that there isn't much copying going on.

True laziness is hard work

In reply to Re: Hash of arrays generation by GrandFather
in thread Hash of arrays generation by nemesisgus

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.