More combiner tags will be necessary if new datatype *construction
functions* discussed in the miscellany chapter and others are voted
I believe that the largest chunk of new datatype constructors are those
mentioned in the i/o chapter (section 10.7 Filetype Constructors). And
I think that they are all "convenience constructors" rather than
"fundamental constructors". That is they don't represent new ways of
putting together datatypes, rather they represent conveniences for
things that the subcommittee believes will either be common or possibly
error prone on the user's part.
I believe that we should distinguish between the two -- the "convenience
constructors" vs the "fundamental constructors" and that the
get-type-envelope and get-type-contents functions should only deal with
the fundamental constructors.
I would consider type-simple-struct and type-congtiguous-struct to be