Oopsie. I'm on drugs - that's my excuse.

(No, really - oral surgery last Wednesday. That's my story, and I'm sticking to it!)

Corrected stuff:

The regular expression:

(?-imsx:(".*?"))

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 \n (0 or more times
                             (matching the least amount possible))
----------------------------------------------------------------------
    "                        '"'
----------------------------------------------------------------------
  )                        end of \1
----------------------------------------------------------------------
)                        end of grouping
----------------------------------------------------------------------
[download]

The point about YAPE::Regex::Explain being useful to someone learning regexes is still perfectly valid, despite my mistake. :-)

Another suggestion: if the whole regex is surrounded by a fully qualified (?xi-sm: ... ) block, then it's likely created by the qr// stringification, and not as presented. I would consider stripping that off and then explain the modes at the end along with any /g /e explanations.