Pattern in lookbehind

Question

My question is related with lookbehinds, I want to find all the first numbers after the word \"this\", I have the following data:

188282 this is an exam

Answer 1

The thing with lookbehinds is that not all languages support variable width lookbehinds (they can't support lookbehinds where what's inside can be of variable number of characters).

What you can do, might be using a lookahead and a capture group:

(?=this[^\d]+(\d+))

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Or maybe the \K regex character which resets a match (if your regex engine supports it).

this[^\d]+\K\d+

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