/* Copyright (c) 2013 Microsoft Corporation. All rights reserved. Released under Apache 2.0 license as described in the file LICENSE. Author: Leonardo de Moura */ #pragma once #include "expr.h" namespace lean { /** \brief Return true if the given expression has free variables. */ bool has_free_vars(expr const & a); inline bool closed(expr const & a) { return !has_free_vars(a); } }