Re: Naming of Tagged Types and Associated Packages

["John G. Volan" <johnvolan@sprintmail.com>]

Matthew Heaney wrote:
> 
> My philosophy is to use the name _Type only as a last resort, as it has
> a sort of generic quality to it.  

Funny, I'd say its precisely this quality that should make _Type the
*first* resort! :-)  It's so generally applicable as a type-marking
suffix one might as well use it everywhere...

> That sometimes turns out to be useful,
> as in the example above.  Some guys name generic formal types _Type, for
> exactly that reason.

I'd say, don't treat generic formal types any differently than normal
types: Mark 'em all with "_Type"!  One nice feature of Cohen style is
that it results in a clearly-readable distinction between generic formal
parameter passing and subprogram parameter passing, which otherwise are
syntactically identical (in Ada):

  -- Generic formal parameter passing:
  package Doctor_Lists is new
    Lists (Item_Type => Doctors.Doctor_Type);
           -- it's clear that the parameter 
           -- being passed is a _type_
  ...
  Doctor_List : Doctors_Lists.List_Type;
  Doctor : Doctors.Doctor_Type;
  ...
  Doctor_Lists.Append (List => Doctor_List, Item => Doctor);
                       -- it's clear that the parameters
                       -- being passed are _objects_

-- 
indexing
   description: "Signatures for John G. Volan"
   self_plug: "Ex Ada guru", "Java 1.1 Certified", "Eiffelist wannabe"
   two_cents: "Java would be even cooler with Eiffel's assertions/DBC, %
              %generics, true MI, feature adaptation, uniform access, %
              %selective export, expanded types, etc., etc..."
class JOHN_VOLAN_SIGNATURE inherit SIGNATURE invariant
   disclaimer: not (opinion implies employer.opinion)
end -- class JOHN_VOLAN_SIGNATURE