/^chars(?!.*that).*this.*(?<!whatever)$/

[download]

If "whatever" is actually a pattern that can match more than a single length of string, then instead use: 

/^chars(?!.*that).*this(?!.*whatever$)/

[download]

And note that the (?!.*that) part doesn't need to be repeated.

- tye        

In reply to Re: Problem with negative lookahead at end of string by tye
in thread Problem with negative lookahead at end of string by olivierp

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