Ocaml parser for applying a function

I have a file, parser.mly, which has the following

%{open Ast%}(* Ast holds the abstract syntax tree type definitions. *)%token EOF%token OR%left OR%start <Ast.prog> prog%% prog:  | e = expr; EOF {e};expr:  | e1 = expr; OR; e2 = expr { Binop(Or, e1, e2) };

I'm trying to add a definition for function application.

However, function application doesn't have its own token. It's just an expression followed by another expression.

When I try to code this with something like

| e1 = expr; e2 = expr { App(e1, e2) }

very understandably, the compiler gives the error message that 2 states have shift/reduce conflicts, because this kind of rule introduces ambiguity.

Now I can eliminate the ambiguity that comes with OR tokens by declaring them left-associative. But how do I do it in this case, where no token can be declared to be left-associative?