Parse scalar expressions with source spans

src/main.ml

@@ -85,25 +85,26 @@ let load_source path =
   Diagnostic.set_file path;
   Native.read_file path
 
+let parse_source path = Parse.expression (load_source path)
+
 let frontend_unavailable () =
-  Diagnostic.error Location.none "the delta source frontend is not implemented in this revision"
+  Diagnostic.error Location.none "the delta pipeline beyond parsing is not implemented in this revision"
 
 let check path =
-  ignore (load_source path);
-  frontend_unavailable ()
+  ignore (parse_source path)
 
 let dump stage path =
-  ignore (load_source path);
-  ignore stage;
+  ignore (stage);
+  ignore (parse_source path);
   frontend_unavailable ()
 
 let emit path output =
-  ignore (load_source path);
+  ignore (parse_source path);
   ignore output;
   frontend_unavailable ()
 
 let build path output =
-  ignore (load_source path);
+  ignore (parse_source path);
   ignore output;
   frontend_unavailable ()