add translation of non-struct constructor expressions

src/mlw/rust_printer.ml

@@ -48,6 +48,7 @@ module Rust = struct
     | Evar of pvsymbol
     | Efield of expr * ident
     | Etup of expr list
+    | Eenum of rsymbol * expr list
     | Estruct of rsymbol * rsymbol list * expr list (* Rs { r1: e1, r2: e2 } *)
     | Eblock of expr list
     | Ecall of rsymbol * expr list
@@ -105,6 +106,7 @@ module Rust = struct
     | Elet (p, e1, e2) -> Elet (p, clean_expr e1, clean_expr e2)
     | Efield (e, id) -> Efield (clean_expr e, id)
     | Etup el -> Etup (clean_list el)
+    | Eenum (rs, el) -> Eenum (rs, clean_list el)
     | Estruct (rs, fl, el) -> Estruct (rs, fl, clean_list el)
     | Ematch (e, bl) ->
         let clean_bl = List.map (fun (p, e) -> (p, clean_expr e)) bl in
@@ -269,9 +271,14 @@ module MLToRust = struct
         | None, None, _ when is_rs_tuple rs ->
             Rust.Etup (el)
         | None, None, [e1] when isfield -> Rust.Efield (e1, rs.rs_name)
-        | None, None, _ when isconstructor () ->
+        | None, None, el when isconstructor () ->
             (match get_record info rs with
-            | [] -> raise (TODO "Constructor (el)")
+            | [] ->
+                let maybe_box rs i e =
+                  if Sbe.contains boxes.box_enum (rs.rs_name, i) then box_expr e
+                  else e in
+                let el = List.mapi (maybe_box rs) el in
+                Rust.Eenum (rs, el)
             | rsl ->
                 let maybe_box (rs: rsymbol) (e: Rust.expr) =
                   if Sid.contains boxes.box_fields rs.rs_name then box_expr e
@@ -364,6 +371,7 @@ module MLToRust = struct
     | Rust.Elet (_, e1, e2) -> map_and_union [e1;e2]
     | Rust.Efield (e, _) -> discover_lts_tvs_expr e
     | Rust.Etup el -> map_and_union el
+    | Rust.Eenum (_, el) -> map_and_union el
     | Rust.Estruct (_, _, el) -> map_and_union el (* TODO check rsymbols*)
     | Rust.Ematch (e, bl) ->
         let bel = List.map (fun (_, e) -> e) bl in
@@ -707,6 +715,7 @@ module Print = struct
           (print_list comma (print_ty info)) argl
           (print_ty info) res
 
+  (* TODO why not use rs.rs_name? *)
   (* find ident of a struct by its rsymbol *)
   let struct_id rs =
     (match rs.rs_cty.cty_result.ity_node with
@@ -755,6 +764,10 @@ module Print = struct
     | Efield (e, id) ->
         fprintf fmt "%a.%a" (print_expr info) e (print_lident info) id
     | Etup el -> fprintf fmt "(%a)" (print_list comma (print_expr info)) el
+    | Eenum (rs, []) -> print_uident info fmt (struct_id rs)
+    | Eenum (rs, el) ->
+        fprintf fmt "%a (%a)" (print_uident info) (struct_id rs)
+        (print_list comma (print_expr info)) el
     | Estruct (rs, fl, el) ->
         fprintf fmt "@[<hov 2>%a { %a }@]" (print_uident info) (struct_id rs)
         (print_list2 semi colon (print_rs info) (print_expr info)) (fl, el)