Just for the sake of completeness, here's an alternative:

  /^(?:(?!evil|bad|wrong).)*\z/

[download]

Eimi's solution is much faster for the problem as given, but this approach gives more control - if your problem becomes any more complex in the future it's a useful trick to have available.

Hugo

In reply to Re^3: Blacklisting with a Regular Expression by hv
in thread Blacklisting with a Regular Expression by BenjiSmith

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