Could anyone offer some advice on the following.

The below code demonstrates the problem. Basically arrays @a and @b are the same so as the program iterates through array @a checking each value against array @b, grep should return true every time.

Trouble is it doesn't seem to when unusual characters are in the string, in this example brackets chars ( or ).

I'm sure this is something to do with the string being expanded inside the grep statment before grepping occurs but I'd just like to understand if this *is* why it's going wrong just why does it do it like that and what's the best way around it.

I wouldn't like to have to escape every character before grepping if at all possible.

Thanks. 

use strict;

my (@a,@b);
@a=@b=("test1","test2(X)");

foreach(@a) {
    my $x=$_;
    if(grep(/^$x$/,@b)) {
        print "\"$x\" exists in \"@b\"\n";
    } else {
        print "\"$x\" doesn't exist in \"@b\"\n";
    }
}

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In reply to Grep expansion problem by Lyndley

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