Lookaheads and grouping

[marklarah]

Hey hey dudes

 

So I'm fairly new to regex (I've avoided having to write my own expressions up till now lol)

 

So I have a big expression that matches URLs, but I don't want it to match if it's proceeded by something.

 

To boil it down and put it simply, something like this

([a-z]+)(?!( hi))

with string "hello hi" would match "hell", but how would I make it so it matches nothing? ie how do I put everything else that I'd normally test for together in a group or something, with a conditional that if everything is proceeded by something else, the whole thing returns no matches. Hope I'm making myself clear....

 

Thanks!

 

Mark

[abareplace]

Hi, Mark,

 

you should check that the word ends here:

 

([a-z]+)\b(?!( hi))

 

\b is a word boundary (in this case, the end of the word).

[marklarah]

You sir, are a god amongst men.

 

Many thanks.