If you're using a module from CPAN which seemingly misbehaves, your
best chances are to check its source code.
But where is it installed? If you take Date::Calc, for example,
would you know that it's located in
wpm takes a module name as a parameter and quickly determines where it
is installed by walking the @INC array. The module name is expected in
the same format in which Perl's use command expects them -- without
the *.pm postfix and with double-colons (::) as hierarchy separators.