Hi,

there's a funny regex in the source of TWiki we're trying to use here (and failing - that's why I'm going through the source) where it parses an RCS file: 

/^([0-9]+)\.([0-9]+)\s+date\s+(\d\d(\d\d)?(\.\d\d){5}?);$/o

[download]
note the last part: 
(\.\d\d){5}?;

[download]
I've never seen quantifiers strung together like that... I've checked the Camel Book - it doesn't specifically cover this case, but its talk about "quantified atoms" seems to suggest that the construct is illegal. OTOH since it does compile, so I would be tempted to interpret it as 
((\.\d\d){5})?;

[download]
- but that's not how it matches... :-( It does match 
.01.02.03.04.05;

[download]
but not a lone 
;

[download]
I get a feeling there's something wrong with this regex - what do you think?

In reply to Regex quantifiers composed? by Anonymous Monk

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.