+ | Ast.Ident (id,_) when clear_interpretation -> Ast.Ident (id,`Ambiguous)
+ | Ast.Symbol (s,_) when clear_interpretation -> Ast.Symbol (s,None)
+ | Ast.Num (n,_) when clear_interpretation -> Ast.Num (n,None)
+ | ( Ast.Ident _
+ | Ast.Symbol _
+ | Ast.Num _