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I agree with the earlier responses that a regex is a better solution that split here. However, I noticed that all the suggested regex solutions access $1 et al. without making sure the regex match succeeded. A failed match does not reset the special regex variables -- they keep their values from the previous successful match!

Here's one way to check the success of the match. Of course, you can change the structure, but the basic idea is to only access $1 et al. if the match succeeds.

my $inLine = "RPC, rpc #001b, (1987)"; my $year; if ($inLine =~ /\((\d+)\)/) { $year = $1; } else { die "No year found in '$inLine'.\n"; } print "Found year '$year' in '$inLine'.\n";

 

Here's a demonstration of a bug caused by not checking the success of the match.
my $inLine = "RPC, rpc #001b, 1987"; $inLine =~ /(#\d+[a-z])/; my $rpcNum = $1; print "Found rpc num '$rpcNum' in '$inLine'.\n"; $inLine =~ /\((\d+)\)/; my $year = $1; print "Found year '$year' in '$inLine'.\n";
This produces the following output.
Found rpc num #001b in RPC, rpc #001b, 1987. Found year #001b in RPC, rpc #001b, 1987.

In reply to Re: split question by chipmunk
in thread split question by Anonymous Monk

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