fix syntax according to https://github.com/HaxeFoundation/haxe/issues/11787

Index: src/context/typecore.ml
--- src/context/typecore.ml.orig
+++ src/context/typecore.ml
@@ -294,7 +294,7 @@ let add_local ctx k n t p =
 			begin try
 				let v' = PMap.find n ctx.locals in
 				(* ignore std lib *)
-				if not (List.exists (ExtLib.String.starts_with p.pfile) ctx.com.std_path) then begin
+				if not (List.exists (fun s -> ExtLib.String.starts_with p.pfile s) ctx.com.std_path) then begin
 					warning ctx WVarShadow "This variable shadows a previously declared variable" p;
 					warning ~depth:1 ctx WVarShadow (compl_msg "Previous variable was here") v'.v_pos
 				end
