There are many resources on this in the tutorials-section.

Another resource I find helpful is this online analyzer. It gives you at least a hint where to search for - e.g. in your second example it shows that the ?= is a ZeroWidthPositiveLookahead. Google it to gain deeper knowledge ;-)

HTH, Rata

In reply to Re: Reading Reg Exp by Ratazong
in thread Reading Reg Exp by bharatbsharma

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