Regex, select the closest match

Question

Suppose the following sequence of words

BLA text text text text text text BLA text text text text LOOK text text text BLA text text BLA 

I would like to do to extract the text from the BLA in the LOOK, but the BLA that is closest to viewing. That is, I would like to receive

 BLA text text text text LOOK 

How can I do this with regular expressions? I have one solution that works, but which is extremely inefficient.

 BLA(?!.*?BLA.*?LOOK).*?LOOK 

Is there a better and more efficient way to match this pattern?

What I would like to do is: I would match the BLA and then go into lookahead until a positive reverse expression with LOOK or a negative look with BLA appears. But I do not know how to make this a regular expression.

As an engine, I use re in python.

Answer 1

 BLA(?:(?!BLA).)*?LOOK 

Try it. Check out the demo.

https://regex101.com/r/fA6wE2/12

or

 BLA(?:(?!BLA|LOOK).)*?LOOK 

To be more secure.

Answer 2

just find the text between LOOK and BLA without BLA

 In : re.search(r'BLA [^(BLA)]+ LOOK', 'BLA text text text text text text BLA text text text text LOOK text text text BLA text text BLA').group() Out: 'BLA text text text text LOOK' 

:-)