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With any reasonably large set of keywords, this is maybe not the best idea. Not only does alternation within the regex really slow the engine down ( Camel 3 explain why quite well ) , but you will likely exceed the maximum allowed size of a single regex quickly.

I would suggest using qr//, which was introduced in perl 5.5. It allows you to store a compiled regex in a scalar. Given all the keywords are stored in @words, create a hash ( wait for it ) called %regex like this:

%regex = map { $_ => qr/$_/ } @words;
Then, modify the inner most while loop to look like
LINE: while ( <FILE> ) { for my $word ( @words ) { my $pat = $regex{$word}; next unless ( /$pat/ ); print "$word was found\n"; last LINE; } }
The last LINE part is assumes you can stop processing the file as soon as one pattern matches. Remove it if you want to test all the keywords against each line in the file.

mikfire


In reply to RE: Re: Search Algorithm by mikfire
in thread Search Algorithm by tenfourty

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