Re: Angle brackets and regex problem

You've told it to match one character not an > (which 1 is), one or more digits (which 3 is), zero or more lower case letters (which nothing is), and one character that's not < (which a is). Wherein lies the problem?

And of course there's the standard jibe that in general you want to use something like HTML::TreeBuilder or the like to parse HTML, not regexen.

Update: Curse you, ~~Red Baron~~merlyn. :)

And a hopefully useful pointer: YAPE::Regex::Explain can be helpful for obtaining a prose explanation of just what your regex means. Using it on your regex produces this:

perl -MYAPE::Regex::Explain -le 'print YAPE::Regex::Explain->new( qr/(
+[^>]\d+[a-z]*[^<])/ )->explain'
The regular expression:

(?-imsx:([^>]\d+[a-z]*[^<]))

matches as follows:
  
NODE                     EXPLANATION
----------------------------------------------------------------------
(?-imsx:                 group, but do not capture (case-sensitive)
                         (with ^ and $ matching normally) (with . not
                         matching \n) (matching whitespace and #
                         normally):
----------------------------------------------------------------------
  (                        group and capture to \1:
----------------------------------------------------------------------
    [^>]                     any character except: '>'
----------------------------------------------------------------------
    \d+                      digits (0-9) (1 or more times (matching
                             the most amount possible))
----------------------------------------------------------------------
    [a-z]*                   any character of: 'a' to 'z' (0 or more
                             times (matching the most amount
                             possible))
----------------------------------------------------------------------
    [^<]                     any character except: '<'
----------------------------------------------------------------------
  )                        end of \1
----------------------------------------------------------------------
)                        end of grouping
----------------------------------------------------------------------
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Comment on Re: Angle brackets and regex problem Download Code

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Re^2: Angle brackets and regex problem by emav (Pilgrim) on Jan 05, 2007 at 17:36 UTC
It's official! I'm blind! :( I expected it not to find a match. Oh, dear! So embarrassing!	[reply]
Re^3: Angle brackets and regex problem by ikegami (Patriarch) on Jan 05, 2007 at 17:40 UTC
If you ever wonder what something matched, you can use `my $at = $-[0]; my $matched = substr($test, $at, $+[0]-$at); warn(Matched "$matched" at $at\n");` [download] Alternatively, you could pass the argument `-Meval=debug` to `perl`. (e.g. `perl -Mre=debug script.pl`). It produces a detailed (i.e. long) report of all regexp activities. References: `@-` and `@+` are documented in perlvar. `-Mre=debug` adds `use re 'debug';` to your program. See re.	[reply] [d/l] [select]