Positive Lookahead
Lookahead, a powerful feature in regex, is not just for the faint of heart. It's for the bold, the fearless, the ones who dare to dream of a world where matches never end. With Positive Lookahead, you can peek into the future, see the end from the beginning.
Examples
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Match any string that ends with a 'z' but only if it's followed by 'o'
(\w+)(?=z)$Match: foxz Match: foxzoo Does not match: fox -
Match any string that starts and ends with 'x'
^x(?=x$)Match: xax Match: xaxx Does not match: abc