Beware this question may be pointless or basic but it is bugging me. What is the differance between 
my @foo;
my %bar;
my $yuk;

and 
my @foo=();
my %bar=();
my $yuk={};

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Does pre declaring variables before you use them have any memory/performance benefit for the interpreter by providing type information. I know in other strongly typed languages you should always declare the type of your variable but does it matter in perl or am I doing it by prepending @ or % or $.

Also is putting a 'my' call inside a loop to clear the variable advisable?

In reply to Predeclaration by hakkr

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