You've hit on one of the improvements that Perl makes over C (and I've developed in both languages for some time).

In C, that code is meaningless, because the allocated address is on the stack, and that address disappears as soon as you return from the routine. But, as wise brother moritz has pointed out, in Perl, this allocation comes from the heap and not the stack, thus it's still available when the routine returns.

And this is a very useful feature. In C, you'd have to do something convoluted like assign some memory from the heap, pass that address into the routine, and have the routine write to the address that's been passed in, trusting that there's no buffer overrun. Ugh.

Perl just does it better! :)

Alex / talexb / Toronto

Thanks PJ. We owe you so much. Groklaw -- RIP -- 2003 to 2013.


In reply to Re: Why does Perl allow you to return array references to variables in local scope? by talexb
in thread Why does Perl allow you to return array references to variables in local scope? by MrSnrub

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.