unikernel/duniverse/ppxlib_jane/src/language_extension_kernel.mli

@@ -0,0 +1,78 @@
+(*_ This file is manually imported from the Jane Street version of the
+   OCaml compiler. Don't make changes directly to this file. *)
+[@@@ocaml.warning "-missing-record-field-pattern"]
+
+open! Shadow_compiler_distribution
+
+(** Language extensions provided by the Jane Street version of the OCaml
+    compiler.
+
+    This is the signature of the {!Language_extension_kernel} module that is
+    directly imported into [ppxlib_jane].
+*)
+
+type maturity =
+  | Stable
+  | Beta
+  | Alpha
+
+(** The type of language extensions. An ['a t] is an extension that can either
+    be off or be set to have any value in ['a], so a [unit t] can be either on
+    or off, while a [maturity t] can have different maturity settings. *)
+type _ t =
+  | Comprehensions : unit t
+  | Mode : unit t
+  | Unique : unit t
+  | Include_functor : unit t
+  | Polymorphic_parameters : unit t
+  | Immutable_arrays : unit t
+  | Module_strengthening : unit t
+  | Layouts : maturity t
+  | SIMD : unit t
+  | Labeled_tuples : unit t
+  | Small_numbers : unit t
+
+module Exist : sig
+  type 'a extn = 'a t
+  type t = Pack : _ extn -> t
+
+  val all : t list
+end
+with type 'a extn := 'a t
+
+module Exist_pair : sig
+  type 'a extn = 'a t
+  type t = Pair : 'a extn * 'a -> t
+end
+with type 'a extn := 'a t
+
+(** Print and parse language extensions; parsing is case-insensitive *)
+val to_string : _ t -> string
+
+val of_string : string -> Exist.t option
+val pair_of_string : string -> Exist_pair.t option
+val maturity_to_string : maturity -> string
+
+(** Check if a language extension is "erasable", i.e. whether it can be
+    harmlessly translated to attributes and compiled with the upstream
+    compiler. *)
+val is_erasable : _ t -> bool
+
+module type Language_extension_for_jane_syntax = sig
+  (** This module type defines the pieces of functionality used by
+      {!Jane_syntax_parsing} and {!Jane_syntax} so that we can more easily
+      import these modules into [ppxlib_jane], without also including all of the
+      [Language_extension] machinery.
+
+      It includes the stateful operations that {!Jane_syntax_parsing} relies on.
+      This limits the number of bindings that [ppxlib_jane] needs to have mock
+      implementations for.
+  *)
+
+  type nonrec 'a t = 'a t
+
+  (** Check if a language extension is currently enabled. *)
+  val is_enabled : _ t -> bool
+
+  val is_at_least : 'a t -> 'a -> bool
+end