Is it possible to join these two regex expressions into one?

i have the following two regular expressions (in order btw).

1. ^~/buying/(.*)\?(.*)   => foo= group 1  baa= group 2.
2. ^~/buying/(.*)         => foo= group 1  baa= nothing/empty/null/baibai

What's i'm trying to do is, if the url has a questionmark, then split it into two groups. Otherwise, just throw all the stuff into the first group.

the reason why the order is important for me,开发者_StackOverflow is that if i switch them round, the '?' regex will never get fired because the #2 expression (above) will catch all.

So .. can this be re-fixed?

NOTE: I have tried using this website** to help me debug/tweak .. but I can't figure it out.

** I have no affiliation with that site.

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try this:

^~/buying/([^?]*)\??(.*)

([^?]*) - Captures the first group, which doesn't contain a question mark.
\?? - Optional question mark.
(.*) - Optional second group - can be empty.

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How about just making the second part optional (untested):

^~/buying/([^\?]*)(?:\?(.*))?

The ?: is there to prevent the optional part (the part you need plus the question mark) from capturing.

Edit: Because of greediness, you need to use either the negated character class [^\?] or make it lazy. (The negated character class is preferred because it reduces backtracking.)

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also you can join like this, easier to understand.

^~/buying/(.*)(\?(.*))?$