i don't understand this RE example from the documentation
johnjsal at NOSPAMgmail.com
Mon May 8 22:36:36 CEST 2006
Ok, I've been staring at this and figuring it out for a while. I'm close
to getting it, but I'm confused by the examples:
Will try to match with yes-pattern if the group with given id or name
exists, and with no-pattern if it doesn't. |no-pattern is optional and
can be omitted.
For example, (<)?(\w+@\w+(?:\.\w+)+)(?(1)>) is a poor email matching
pattern, which will match with '<user at host.com>' as well as
'user at host.com', but not with '<user at host.com'. New in version 2.4.
group(1) is the email address pattern, right? So why does the above RE
match 'user at host.com'. If the email address exists, does the last part
of the RE: (?(1)>) mean that it has to end with a '>'?
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