Modulino package name added to @_

Question

Consider the following basic Perl modulino:

#!/usr/bin/perl -l
package Toto;

__PACKAGE__->run(@ARGV) unless caller();

sub run 
{
  print "@ARGV";
  print "@_";
}

1;

If I run it on the command line, I get:

$ ./Toto.pm 1 2 3
1 2 3
Toto 1 2 3

If I call it from a test:

$ perl -MToto -le 'Toto::run(1,2,3)'    
#first line blank - no ARGV set
1 2 3

In other words, the contents of @_ inside run() changes depending on how the function is called.

Can you explain what is going on?

Answer 1

__PACKAGE__->run(@ARGV)

is equivalent to

Toto->run(1,2,3)

This is a class method call. Method calls pass the invocant (the value to which the LHS of the -> evaluated) as the first argument. This differs from

Toto::run(1,2,3)

which is a simple sub call. The following will call run as a sub:

run(@ARGV) unless caller();