Hi Monks, I'm working on the following situation:
# Foo.pm
package Foo;
use strict;
use warnings;
use Bar;
sub foo { warn 'Foo::foo was called' }
Bar->bar;
1;
A package Foo calls Bar's bar() method.
Foo defines foo() method which prints a message to STDERR.
On the other hand, Bar.pm looks as follows:
# Bar.pm
package Bar;
use strict;
use warnings;
sub bar { Foo->foo }
1;
Bar defines bar() method which calls Foo's foo() method.
I executed Foo.pm and confirmed the script output 'Foo::foo was called':
$ ls
Foo.pm Bar.pm
$ perl Foo.pm
Foo::foo was called
This result shows us that Bar can call Foo's foo() method without loading Foo.pm (I mean, without 'use Foo;')
In other words, Bar can call the caller's method ( Foo::foo() ).
If so, why is this possible?
Is this one of well-known specifications?
Which perldoc helps me understand this result?
Sincerely,
Ryo
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