Thanks for taking the time to explain Xiong, and I get the connection now, even though I had to read through everything a few times. Being an obedient student, I always use warnings as well as strict, and note that I get a warning if I try to print $hash{pensionbalance} and also if I say something like: 
my $debts = 100;
my $money_left = $debts - $hash{pensionbalance};
# Use of uninitialized value in subtraction (-)

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Am I safe to assume then that use warnings will always keep me safe?

In reply to Re^5: RFC: Tutorial: use strict; now what!? by tangent
in thread RFC: Tutorial: use strict; now what!? by Xiong

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