I was working on something, and then this 'small trick' made me stuck for couple of minutes. I just don't want everyone to waste this couple of minutes, which is so precious, so I come to share with you.

The problem is with Data::Dumper, it appears to be a little bit too smart. Because my program is relatively big, and what I was modifing was hundreds lines away from Dumper, so at first I even didn't think that, the trouble was caused by Dumper, until I suddenly started to suspect ... Now I simplify the trick and share with you: 
use Data::Dumper;

$hash = {1 => "(\\d+)"}; #the value is (\d+)
print "result from print Dumper:\n"; 
print Dumper($hash); #which prints (\\d+), this really confused me
print "\n";
print "actual value stored:\n";
print $hash->{1};

[download]
I hope Dumper can simply tell me the truth, not to play smart, and confuse me. Although that \\ makes sense to me now, but what is the benefit to display in this way?

Now, is there an option in Dumper, that I can turn this off.

In reply to Data::Dumper style by pg

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