That doesn't bother me. The OP seemed to be discussing the validity and practicality of single-entry character classes. And I believe he was discussing them in the context of the [....] operator in a regexp. The backslash CC's and property CC's are already 'single entry', so probably not really so relevant to the discussion, particularly where they can stand-alone outside of a user-defined character class.

Certainly the POSIX classes constitute "single entries". And that's definitely another good argument for why single-entry character classes are practical, and should be legal (which, of course, they are).

The negated character class of a single entry just happened to be the first example that jumped to my mind. Your POSIX thought is great too.


Dave

In reply to Re^3: Why would one want in a regex a class with only a single entry? by davido
in thread Why would one want in a regex a class with only a single entry? by ack

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.