/^(?:[^f]+|f(?!oo))*$/;   # Matches strings not containing 'foo'.

    /^(?:(?!PATTERN).)*$/;    # Matches strings not containing PATTERN
+.

[download]
The top one is reasonably fast, the bottom one is slow, but works for all patterns.

Abigail

In reply to Re: How do I write a regex for 'does not contain' a string. by Abigail-II
in thread How do I write a regex for 'does not contain' a string. by IraTarball

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