Sub::Identify allows you to retrieve the real name of code references.
It provides six functions, all of them taking a code reference.
sub_name returns the name of the code reference passed as an
argument (or __ANON__ if its an anonymous code reference),
stash_name returns its package, and sub_fullname returns the
concatenation of the two.
get_code_info returns a list of two elements, the package and the
subroutine name (in case of you want both and are worried by the speed.)
In case of subroutine aliasing, those functions always return the
get_code_location returns a two-element list containing the file
name and the line number where the subroutine has been defined.
is_sub_constant returns a boolean value indicating whether the
subroutine is a constant or not.