Calling internal functions - foo::bar() ?

[James Hague]

Does the compiler not take advantage of functions being internal to a
module?  For example, if a function always returns a tuple which is
immediately unpacked, then the tuple construction can be avoided and
the values returned in Erlang registers.  At least I recall reading
about this somewhere.

If this is the case, then you wouldn't be able to call internal
functions directly.