40 lines
1.6 KiB
C++
40 lines
1.6 KiB
C++
/*
|
|
Copyright (c) 2014 Microsoft Corporation. All rights reserved.
|
|
Released under Apache 2.0 license as described in the file LICENSE.
|
|
|
|
Author: Leonardo de Moura
|
|
*/
|
|
#pragma once
|
|
#include "util/lazy_list.h"
|
|
#include "kernel/environment.h"
|
|
#include "kernel/constraint.h"
|
|
#include "kernel/type_checker.h"
|
|
|
|
namespace lean {
|
|
/**
|
|
\brief A unifier_plugin provides a simple way to extend the \c unify procedures.
|
|
Whenever, the default implementation does not know how to solve a constraint, it invokes the plugin.
|
|
The plugin return a lazy_list (stream) of possible solutions. Each "solution" is represented as
|
|
a new list of constraints.
|
|
|
|
The method \c delay_constraint is invoked to decide whether the particular constraint should
|
|
be delayed. This is useful when implementing unification plugins
|
|
*/
|
|
class unifier_plugin_cell {
|
|
public:
|
|
virtual ~unifier_plugin_cell() {}
|
|
virtual lazy_list<constraints> solve(type_checker &, constraint const &, name_generator const &) const = 0;
|
|
virtual bool delay_constraint(type_checker &, constraint const &) const = 0;
|
|
};
|
|
|
|
typedef std::shared_ptr<unifier_plugin_cell> unifier_plugin;
|
|
/** \brief Combine two plugins by appending their solutions. */
|
|
unifier_plugin append(unifier_plugin const & p1, unifier_plugin const & p2);
|
|
/** \brief Combine two plugins by taking the solutions of p1, if it is empty, then return solutions of p2 */
|
|
unifier_plugin orelse(unifier_plugin const & p1, unifier_plugin const & p2);
|
|
|
|
environment set_unifier_plugin(environment const & env, unifier_plugin const & p);
|
|
unifier_plugin const & get_unifier_plugin(environment const & env);
|
|
void initialize_unifier_plugin();
|
|
void finalize_unifier_plugin();
|
|
}
|