I actually do all my reg exing using Python's re module. But I imagine Qt's reg exs are compatible enough that I can use them as Python's if someone would care to answer.... I could have asked this question on stackoverflow , but you guys are so friendly & helpful that I thought I'd try here :) Not to mention, it's often so difficult to think of a title for these reg ex questions! I wish to search (and capture group) for: text started and ended with (i.e. enclosed inside) a pair of characters, ** something ** : abc ** this is matching text ** def abc ** this is matching * PLUS this bit ** abc ** this is matching ** but not this ** and this is a new one ** def It's easy to exclude all * s in the middle: \*\*([^*]*)\*\* But what about allowing lone * s while excluding the multi-character sequence ** ? I imagine it's something to do with "zero width lookahead". But reading the explanations of that makes my head hurt. Would someone care to tell me what I need for this, kindly?

@JonB said in Regular expression for *not* a *sequence* of characters : OK, why as few times as possible? That's the effect of ? after + . It make the match non-greedy. If you remove the question mark it will behave as you are expecting

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Regular expression for not a sequence of characters

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V VRonin

@JonB said in Regular expression for *not* a *sequence* of characters:

it now seems to me that it does have such a construct

It does not have a generic way. It has a "line does not contain" or "document does not contain". Say you want to capture stuff inside ** (so \*\*(.+?)\*\*) but exclude the capture if .+? matches foo. I don't think that is possible.

Forget what I said.
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@VRonin , @kshegunov
Thank you both very much for your time & input. I have learnt a lot about these "advanced" regular expressions now. I will not close this thread.
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