RegexdrillNegative lookahead: not starting with un
A regex exercise from Regexdrill. Solve it with a pattern box with live highlighting in your browser, checked against hidden test strings, and it is checked the moment you submit.
The task
The whole line must match. Match lowercase words that do not begin with un.
What this exercise teaches
(?!un)[a-z]+ refuses lines that start with un and accepts any other lowercase word, including u and nun.
A hint if you get stuck
(?!...) fails when the text ahead matches. Put it at the very start.
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