When you put executable perl code into the replacement (right-hand) portion of  s///e, I think you are by nature using "eval" to execute that code. Therefore, you run up against this little detail described in the man page for Switch (under the section heading "LIMITATIONS"):
Due to the way source filters work in Perl, you can't use Switch inside a string "eval".
The reference to "source filters" there has to do with how the Switch module is implemented. When you use it, the code that ends up being executed is actually different in significant ways from the code that you wrote. That's why many people (including the author of the module) advise against using Switch in "production code" (i.e. for anything that needs to be rock-solid and readily maintainable).

As GrandFather pointed out, there are better ways to do what you need to do in this case.

In reply to Re^3: regex switch trouble by graff
in thread regex switch trouble by spx2

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.