Perl Regular Expression Help

I was wondering how to write this regular expression differently:

$line !~ /this that( now| other)/

Here is the catch, I have to use “=~” instead of “!~”. Is there a way of doing this? I can’t seem to figure it out.

What’s happening is I’m passing this pattern into a method where the =~ is hardcoded. I want to match a phrase with a certain prefix (“this that” in this case) but not if it has certain suffixes (" now" or " other" in my above example). I can’t seem to figure this out. Thanks!

Can’t really help but I do find the calcs invaluable.
Regular Expressions

I constantly argue with regexp.

In general it’s not possible to take a RE and convert it a simple RE for the complement language. Although the complement of a regular language is also regular, it might not be simple to specify.

Kids.Net.Au - Encyclopedia > Regular language

I’m just amused that such a topic is found in an encyclopedia for kids. Boy, kids are really smart these days. lol!

What about

$line !~ /this that(^n]|n^o]|no^w])|(^o]|o^t]|ot^h]|oth^e]|othe^r])/