I am attempting to match lines in a huge log files, reading each line into an array then righting it to an email. That part is easy, now they want me to print only certain lines out. I have a 2nd array thats sole job is to be used to match a field. I can do it in with three individual IF statements.

Is there an easier way to do it, with the =~ like $a[1] =~ %b ???? or something that? To compare the field to the entire 2nd array at once?

What language is this?

I am sorry it is in perl

I am looking for a way to compare 1 element of an array $a[1] to another entire array @b

I also could do it with a for loop, isn't there a one liner to do it?

You mean a boolean OR of each element of the second array as the match string? Why not just do that (i.e., just collapse your array into a single string separated by ‘|’)?

To clarify, instead of something like this:
You would have this:

Sounds to me you want the Perl grep: http://perldoc.perl.org/functions/grep.html

I see how you would want grep for the overall email filtering, but I don’t understand how you would use grep for the ORing of each pattern match.

Actually, the orig qn has varied a bit.
I was orig thinking of an answer to post #3 ie 1 element compared to an array.
However, if OP wants to compare a list/array of elements against the input file/array, then combine your approach ie create an ORed regex and use my grep to match against the whole file/array.
Note that this may not be a good idea if the post 1 ('huge file') is accurate.
You'd be doing against 1 rec at a time if its too big to (easily) fit in mem, although I suppose you could do it in blocks of eg 100 lines at a time.

ended up using the for loop. Easiest way to perform all the other tasks that are supposed to be done to the large log file correctly.