Reworking parametric types in CameLIGO and JsLIGO (concrete syntax, CST, pretty-printing)

Motivation and Context

In JsLIO, until now interface types could not be parametric and interface constants could not bear parametric types. This was an oversight. Also, the pretty-printing of parametric types wrongly discarded the parameters. Same with CameLIGO (val id : 'a.'a -> 'a).

Description

Component

• compiler
• website
• webide
• vscode-plugin
• debugger

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Performance improvement (non-breaking change that improves performance)
• None (change with no changelog)

Changelog

Checklist:

• If a new syntax has been introduced, put a message on slack ligo-lsp
• Changes follow the existing coding style (use dune @fmt to check).
• Tests for the changes have been added (for bug fixes / feature).
• Documentation has been updated.
• Changelog description has been added (if appropriate).
• Start titles under ## Changelog section with #### (if appropriate).
• There is no image or uploaded file in changelog
• Examples in changed behaviour have been added to the changelog (for breaking change / feature).

src/stages/ligo_primitive/abstractions.ml

+type 'a t =
+  { ty_binders : Var.Type_var.t list
+  ; kind : Kind.t
+  ; type_ : 'a
+  }
+[@@deriving eq, compare, yojson, hash, fold, map, iter, sexp]
+(* Lambda (a : kind). term *)
+
+let pp_forall f ppf { ty_binders; kind; type_ } : unit =
+  Format.fprintf
+    ppf
+    "∀ (%a) : %a . %a"
+    Simple_utils.PP_helpers.(list_sep_d Var.Type_var.pp)
+    ty_binders
+    Kind.pp
+    kind
+    f
+    type_
+
+
+let pp_type_abs f ppf { ty_binders; kind; type_ } : unit =
+  Format.fprintf
+    ppf
+    "funtype (%a) : %a . %a"
+    Simple_utils.PP_helpers.(list_sep_d Var.Type_var.pp)
+    ty_binders
+    Kind.pp
+    kind
+    f
+    type_