Please, closure on language expression types & inference

[Anton-Latukha]

Currently, Nix Type inference is a completely separate type subsystem from language semantics:

On: (2021-05-31)

Notice there are Expr.Types that are language basis & Type.Type that is an inference basis.

They are completely separate currently. It is redunculous that Type.Type does not have ANY import from HNix.

They (Expr.* -> Types.*) need to share the maximum types. It would lead to #187 almost directly.

A good start is variable names.

In the type system, variable names are variable names.

[Anton-Latukha]

Also Lint type system seems strongly related to Type.Type inference.

[Anton-Latukha]

#294 is a first stage.

See: johnchildren@7065a91