I haven't checked, but look-around assertions have certainly been around for many years, perhaps more than a decade. Can they really still be considered to be 'advanced'?

Also, the  (?<!\?) and  (?!\?) assertions seem to me to perfectly express the notions 'not preceded by...' and 'not followed by...', respectively. Are they not preferable to the somewhat convoluted logic of your example code? (Admitedly, this may be largely a matter of taste.)

In reply to Re^2: Simple regex question by AnomalousMonk
in thread Simple regex question by ultranerds

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