I use quite a bit of generated code in my program (meaning Perl code that is assembled in a string then eval-ed), for example, when generating argument validator code using Data::Sah.

This turns out to be rather annoying when debugging warning/error messages. Perl only shows the filename as "(eval NUMBER)", for example: 

perl -wE'eval "1+1; 1"; eval "\n; 1+1; 2"'
Useless use of a constant (2) in void context at (eval 1) line 1.
Useless use of a constant (2) in void context at (eval 2) line 2.

[download]

It would be slightly more helpful if there were a way to change the filename into something more descriptive, so the warn/error message can be something like: 

Useless use of a constant (2) in void context at (validator code for X
+ generated by Foo/Bar.pm line 234) line 1.
Useless use of a constant (2) in void context at (validator code for Y
+ generated by Foo/Baz.pm line 99) line 2.

[download]

In reply to Changing "filename" of eval-ed code by perlancar

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.