I am trying to understand the correct use of »atomic grouping« a.k.a. »independent subexpressions« a.k.a. »non-backtracking subpattern« [this are the terms I found for the same thing, which doesn't make it less complicate]
egrep '123(?>fruit|juiceomatic)machine'means: look for
- BUT stop trying to match [the rest of]
the round brackets' content if
123is followed by anything else than
Is this correct? Did I miss something important?
I ask this because I got to the expected results most of the time but I am not 100% sure if this is because I did it right or I just made lucky guesses.