It is printing 11 because you have the: 

my $in_arg=@_;

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Which is giving scalar context to the assignment from @_ which puts the length of the array in $in_arg you want to do either: 
my ( $in_arg ) = @_;

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or 
my $in_arg = shift;

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There is a difference between the two related to the side-effects but you won't notice it in your code.

/J\

In reply to Re: My first module by gellyfish
in thread My first module by tamaguchi

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