What is the regular expression for does not contain

[melvin7020]

I have a number of advanced filters that used regular expressions. I would like to replicate the “does not contain” filter. I think it is something to do with negative lookaheads like (?!..) but have not worke dout how to do that. Also is there something about the e flavour of regex used in libra office being different to that used elsewhere. I have tried
(?!blue$)
(?=((?!blue/).)*$)
both of these give me 220 results while the “does not contain” gives me 358 results.

[melvin7020]

delete duplicat post

[mikekaganski]

@melvin7020

is there something about the e flavour of regex used in libra office

ICU regex engine is used in LibreOffice, with its syntax.

Maybe this could work: regex - Regular expression that doesn't contain certain string - Stack Overflow

[melvin7020]

delete duplicate post

[melvin7020]

fabulous. That worked.
^((?!blue).)*$