the point is rather that at run time the variable doesn't exist any more in your example.

Exactly. And the reason it doesn't exist is because it wasn't captured. That would have kept it alive. You can see the capture increasing the ref count in the following snippet: 

$ perl -MDevel::Peek -e'
   sub f {
      my $x;
      Dump($x);
      my @a = map { sub { $x } } 1..3;
      Dump($x);
   }
   f()
'
SV = NULL(0x0) at 0x817bc90
  REFCNT = 1
  FLAGS = (PADMY)
SV = NULL(0x0) at 0x817bc90
  REFCNT = 4
  FLAGS = (PADMY)

[download]

In reply to Re^3: Accessing lexicals in other scopes dynamically by name by ikegami
in thread Accessing lexicals in other scopes dynamically by name by LanX

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.