The sneaky operative word is "at the level of support from the runtime" by which I mean below the level of what can be done in Perl. On top of this run-time level, one can suppliment this in Perl to add what you see above (and more).

Having said this though it is also true that one can hook into calls and returns. But it so happens in perl5db which is what you are citing above that is not done. Rather, when you specify a function name in a breakpoint, that gets translated into a file and line number and then a breakpoint is set on that, I believe. And as for hooking into the point of return which would be useful, that opportunity is also lost

In reply to Re^2: Identifying a location with finer granularity than a line number by rockyb
in thread Identifying a location with finer granularity than a line number by rockyb

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.