[Caml-list] Question on typing

[Christian RINDERKNECHT <rinderkn@hugo.int-evry.fr>]

Dear list members,

I have a question about typing, but which is not uniquely related to
Caml. 

Could someone tell me the reason why a type variable cannot be used as
a type constructor, like in:

type 'a t = K of bool 'a;;

or

type 'a t = {x : 'a 'a};;

I suspect non-decidability of type inference (higher-order
unification), but I am not an expert of that topic. Also, is type
verification undecidable? Is it due to functional types? What happen
is there is no (value) functions?

Best regards,

-- 

Christian

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