remove E_skip from core

src/passes/6-sugar_to_core/sugar_to_core.ml

@@ -85,7 +85,7 @@ let rec compile_expression : I.expression -> O.expression result =
       let%bind rhs = compile_expression rhs in
       let%bind let_result = compile_expression let_result in
       return @@ O.E_let_in {let_binder=(binder,ty_opt);inline;rhs;let_result}
-    | I.E_skip -> return @@ O.E_skip
+    | I.E_skip -> ok @@ O.e_unit ~loc:e.location ()
     | I.E_constructor {constructor;element} ->
       let%bind element = compile_expression element in
       return @@ O.E_constructor {constructor;element}
@@ -270,7 +270,6 @@ let rec uncompile_expression : O.expression -> I.expression result =
     let%bind rhs = uncompile_expression rhs in
     let%bind let_result = uncompile_expression let_result in
     return @@ I.E_let_in {let_binder=(binder,ty_opt);inline;rhs;let_result}
-  | O.E_skip -> return @@ I.E_skip
   | O.E_constructor {constructor;element} ->
     let%bind element = uncompile_expression element in
     return @@ I.E_constructor {constructor;element}

src/passes/8-typer-new/typer.ml

@@ -446,10 +446,6 @@ and type_expression : environment -> Solver.state -> ?tv_opt:O.type_expression -
   | E_literal (Literal_void) -> (
       failwith "TODO: missing implementation for literal void"
     )
-  | E_skip -> (
-    (* E_skip just returns unit *)
-    return_wrapped (e_unit ()) state @@ Wrap.literal (t_unit ())
-    )
   (* | E_literal (Literal_string s) -> (
    *     L.log (Format.asprintf "literal_string option type: %a" PP_helpers.(option O.PP.type_expression) tv_opt) ;
    *     match Option.map Ast_typed.get_type' tv_opt with

src/passes/8-typer-old/typer.ml

@@ -423,7 +423,7 @@ and type_expression' : environment -> ?tv_opt:O.type_expression -> I.expression
       return (E_variable name) tv'.type_value
   | E_literal (Literal_bool b) ->
       return (E_literal (Literal_bool b)) (t_bool ())
-  | E_literal Literal_unit | E_skip ->
+  | E_literal Literal_unit ->
       return (E_literal (Literal_unit)) (t_unit ())
   | E_literal Literal_void -> return (E_literal (Literal_void)) (t_unit ()) (* TODO : IS this really a t_unit ?*)
   | E_literal (Literal_string s) ->

src/stages/3-ast_core/PP.ml

@@ -58,8 +58,6 @@ and expression_content ppf (ec : expression_content) =
         cases
   | E_let_in { let_binder ;rhs ; let_result; inline } ->    
     fprintf ppf "let %a = %a%a in %a" option_type_name let_binder expression rhs option_inline inline expression let_result
-  | E_skip ->
-      fprintf ppf "skip"
   | E_ascription {anno_expr; type_annotation} ->
       fprintf ppf "%a : %a" expression anno_expr type_expression
         type_annotation

src/stages/3-ast_core/combinators.ml

@@ -121,7 +121,6 @@ let e_matching_bool ?loc a b c : expression = e_matching ?loc a (Match_bool {mat
 let e_accessor ?loc a b = make_expr ?loc @@ E_record_accessor {expr = a; label= Label b}
 let e_accessor_list ?loc a b  = List.fold_left (fun a b -> e_accessor ?loc a b) a b
 let e_variable ?loc v = make_expr ?loc @@ E_variable v
-let e_skip ?loc () = make_expr ?loc @@ E_skip
 let e_let_in ?loc (binder, ascr) inline rhs let_result = 
   make_expr ?loc @@ E_let_in { let_binder = (binder,ascr) ; rhs ; let_result; inline }
 let e_annotation ?loc anno_expr ty = make_expr ?loc @@ E_ascription {anno_expr; type_annotation = ty}

src/stages/3-ast_core/combinators.mli

@@ -83,7 +83,6 @@ val e_matching_bool : ?loc:Location.t -> expression -> expression -> expression
 val e_accessor : ?loc:Location.t -> expression -> string -> expression
 val e_accessor_list : ?loc:Location.t -> expression -> string list -> expression
 val e_variable : ?loc:Location.t -> expression_variable -> expression
-val e_skip : ?loc:Location.t -> unit -> expression
 val e_sequence : ?loc:Location.t -> expression -> expression -> expression
 val e_cond: ?loc:Location.t -> expression -> expression -> expression -> expression
 val e_let_in : ?loc:Location.t -> ( expression_variable * type_expression option ) -> bool -> expression -> expression -> expression

src/stages/3-ast_core/misc.ml

@@ -184,7 +184,7 @@ let rec assert_value_eq (a, b: (expression * expression )) : unit result =
   | (E_application _, _) | (E_let_in _, _)
   | (E_recursive _,_) | (E_record_accessor _, _)
   | (E_look_up _, _) | (E_matching _, _)
-  | (E_skip, _) -> simple_fail "comparing not a value"
+   -> simple_fail "comparing not a value"
 
 let is_value_eq (a , b) = to_bool @@ assert_value_eq (a , b)
 

src/stages/3-ast_core/types.ml

@@ -36,7 +36,6 @@ and expression_content =
   | E_lambda of lambda
   | E_recursive of recursive
   | E_let_in of let_in
-  | E_skip
   (* Variant *)
   | E_constructor of constructor (* For user defined constructors *)
   | E_matching of matching

src/stages/4-ast_typed/types.ml

@@ -40,8 +40,8 @@ and expression_content =
   | E_variable of expression_variable
   | E_application of application
   | E_lambda of lambda
-  | E_let_in of let_in
   | E_recursive of recursive
+  | E_let_in of let_in
   (* Variant *)
   | E_constructor of constructor (* For user defined constructors *)
   | E_matching of matching