Hello monks...

It might just be me being tired, but I have this code...

my @strings;

my $stringFile = <STDIN>; 
chomp $stringFile; 

if ($stringFile eq "") {
    print "No file of exclude strings specified.\n";
    }    
    else {
        open (STRINGFILE, "$stringFile")
        or die "Couldn't open $stringFile:$!\n";
        @strings = <STRINGFILE>;
        }
#BLAH BLAH BLAH

foreach my $file1(@file1only) {
    foreach my $string(@strings) {
        chomp $string;
        unless ($file1 =~ $string) { 
        print OUT $file1;
        last;
        }
    }
}

[download]
If <STRINGFILE> has something in it, everything works fine. But if STRINGFILE isn't specified, @strings is null. I did not expect ($file1 =~ $string) to always be true if the right side of the expression is null.

My instinct is to handle the cases (STRINGFILE exists; STRINGFILE does not exist) with subroutines, but that seems like an awful lot of code to solve a really simple problem.

So any suggestions would be welcome...

In reply to Help with null string behavior in regex? by McMahon

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