How to find the Perl code referenced by this line?

Question

I have inherited some Perl code which contains a line that is mysterious to me:

my $binary = A->current->config->settings('arg1', 'arg2')

Basically, I am not sure how to find the related code. "A" is NOT a variable in the local code so I thought this was a class hierarchy. However I checked the directory structure to see if the following path existed, but there was none:

A/current/config/settings.pm

Is A->current->config->settings guaranteed to be a nested class hierarchy, or could it be something else? For example could config actually be a property or method of a different object A->current?

Any assistance you could lend tracking this down would be greatly appreciated!

Answer 1

A is a class name, you should find it in A.pm. current should be a method of the class, defined under a sub current in A.pm. It returns an object whose config method is being called which returns an object again whose settings method is being called with arguments 'arg1' and 'arg2' (well, in fact, the object itself is the first argument).

In fact, any of the methods can return a class instead of an object, too.

Answer 2

Step through the code in the perl debugger and see where it takes you.

foo->bar is a method call, meaning that there is likely a subroutine called bar defined in the package referred to by foo (or a superclass), and gives you no information about whether there is a package bar or foo::bar.