lean2/src/kernel/environment.h
Leonardo de Moura 25948ac534 refactor(kernel): cleanup interfaces
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
2014-03-18 10:27:57 -07:00

379 lines
15 KiB
C++

/*
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 <iostream>
#include <memory>
#include <vector>
#include <set>
#include <string>
#include <utility>
#include "util/lua.h"
#include "util/shared_mutex.h"
#include "util/name_map.h"
#include "kernel/object.h"
#include "kernel/level.h"
namespace lean {
class environment;
class ro_environment;
class type_checker;
class environment_extension;
/** \brief Implementation of the Lean environment. */
class environment_cell {
friend class environment;
friend class read_write_shared_environment;
friend class read_only_shared_environment;
// Remark: only named objects are stored in the dictionary.
typedef name_map<object> object_dictionary;
typedef std::tuple<level, level, int> constraint;
std::weak_ptr<environment_cell> m_this;
// Children environment management
atomic<unsigned> m_num_children;
std::shared_ptr<environment_cell> m_parent;
// Object management
std::vector<object> m_objects;
object_dictionary m_object_dictionary;
// std::unique_ptr<type_checker> m_type_checker;
std::set<name> m_imported_modules; // set of imported files and builtin modules
bool m_trust_imported; // if true, then imported modules are not type checked.
bool m_type_check; // auxiliary flag used to implement m_trust_imported.
std::vector<std::unique_ptr<environment_extension>> m_extensions;
friend class environment_extension;
// This mutex is only used to implement threadsafe environment objects
// in the external APIs
shared_mutex m_mutex;
environment env() const;
void inc_children() { m_num_children++; }
void dec_children() { m_num_children--; }
environment_extension & get_extension_core(unsigned extid);
environment_extension const & get_extension_core(unsigned extid) const;
unsigned get_max_weight(expr const & e);
void check_name_core(name const & n);
void check_name(name const & n);
void check_level_cnstrs(param_names const & ps, level_cnstrs const & ls);
void register_named_object(object const & new_obj);
optional<object> get_object_core(name const & n) const;
void check_no_mlocal(expr const & e);
void check_type(name const & n, expr const & t, expr const & v);
void check_type(expr const & t);
void check_new_definition(name const & n, param_names const & ps, level_cnstrs const & cs, expr const & t, expr const & v);
bool mark_imported_core(name n);
bool load_core(std::string const & fname, io_state const & ios, optional<std::string> const & mod_name);
bool already_imported(name const & n) const;
/** \brief Return true iff the given file was not already marked as imported. It will also mark the file as imported. */
bool mark_imported(char const * fname);
public:
environment_cell();
environment_cell(std::shared_ptr<environment_cell> const & parent);
~environment_cell();
/** \brief Return true iff this environment has children environments. */
bool has_children() const { return m_num_children > 0; }
/** \brief Return true iff this environment has a parent environment */
bool has_parent() const { return m_parent != nullptr; }
/**
\brief Return parent environment of this environment.
\pre has_parent()
*/
environment parent() const;
/**
\brief Create a child environment. This environment will only allow "read-only" operations until
all children environments are deleted.
*/
environment mk_child() const;
// =======================================
// Environment Objects
/**
\brief Add a new definition n : t := v.
It throws an exception if v does not have type t.
It throws an exception if there is already an object with the given name.
*/
void add_definition(name const & n, param_names const & ps, level_cnstrs const & cs, expr const & t, expr const & v);
void add_theorem(name const & n, param_names const & ps, level_cnstrs const & cs, expr const & t, expr const & v);
void add_definition(name const & n, expr const & t, expr const & v) { add_definition(n, param_names(), level_cnstrs(), t, v); }
void add_theorem(name const & n, expr const & t, expr const & v) { add_theorem(n, param_names(), level_cnstrs(), t, v); }
/**
\brief Add a new definition n : infer_type(v) := v.
It throws an exception if there is already an object with the given name.
*/
void add_definition(name const & n, expr const & v);
/**
\brief Set the given definition as opaque (or not)
\remark It throws an error if \c n is not a definition.
*/
void set_opaque(name const & n, bool opaque);
/**
\brief Add a new fact (Axiom or Fact) to the environment.
It throws an exception if there is already an object with the given name.
*/
void add_axiom(name const & n, param_names const & ps, level_cnstrs const & cs, expr const & t);
void add_var(name const & n, param_names const & ps, level_cnstrs const & cs, expr const & t);
void add_axiom(name const & n, expr const & t) { add_axiom(n, param_names(), level_cnstrs(), t); }
void add_var(name const & n, expr const & t) { add_var(n, param_names(), level_cnstrs(), t); };
/**
\brief Register the given unanymous object in this environment.
The environment assume the object ownership.
*/
void add_neutral_object(neutral_object_cell * o);
/**
\brief Return the object with the given name.
It throws an exception if the environment does not have an object with the given name.
*/
object get_object(name const & n) const;
/**
\brief Find a given object in the environment. Return the null
object if there is no object with the given name.
*/
optional<object> find_object(name const & n) const { return get_object_core(n); }
/** \brief Return true iff the environment has an object with the given name */
bool has_object(name const & n) const { return static_cast<bool>(find_object(n)); }
/**
\brief Type check the given expression, and return the type of \c e in this environment.
*/
expr type_check(expr const & e) const;
/**
\brief Return the type of \c e in this environment.
*/
expr infer_type(expr const & e) const;
/**
\brief Normalize \c e in this environment.
*/
expr normalize(expr const & e) const;
/**
\brief Return true iff \c e is a proposition.
*/
bool is_proposition(expr const & e) const;
/**
\brief Low-level function for accessing objects. Consider using iterators.
*/
unsigned get_num_objects(bool local) const;
/**
\brief Low-level function for accessing objects. Consider using iterators.
*/
object const & get_object(unsigned i, bool local) const;
/** \brief Iterator for Lean environment objects. */
class object_iterator {
std::shared_ptr<environment_cell const> m_env;
unsigned m_idx;
bool m_local;
friend class environment_cell;
object_iterator(std::shared_ptr<environment_cell const> && env, unsigned idx, bool local):m_env(env), m_idx(idx), m_local(local) {}
public:
object_iterator(object_iterator const & s):m_env(s.m_env), m_idx(s.m_idx), m_local(s.m_local) {}
object_iterator & operator++() { ++m_idx; return *this; }
object_iterator operator++(int) { object_iterator tmp(*this); operator++(); return tmp; }
object_iterator & operator--() { --m_idx; return *this; }
object_iterator operator--(int) { object_iterator tmp(*this); operator--(); return tmp; }
bool operator==(object_iterator const & s) const { lean_assert(m_env.get() == s.m_env.get()); return m_idx == s.m_idx; }
bool operator!=(object_iterator const & s) const { return !operator==(s); }
object const & operator*() { return m_env->get_object(m_idx, m_local); }
object const * operator->() { return &(m_env->get_object(m_idx, m_local)); }
};
/**
\brief Return an iterator to the beginning of the sequence of
objects stored in this environment.
\remark The objects in this environment and ancestor
environments are considered
*/
object_iterator begin_objects() const { return object_iterator(m_this.lock(), 0, false); }
/**
\brief Return an iterator to the end of the sequence of
objects stored in this environment.
\remark The objects in this environment and ancestor
environments are considered
*/
object_iterator end_objects() const { return object_iterator(m_this.lock(), get_num_objects(false), false); }
/**
\brief Return an iterator to the beginning of the sequence of
objects stored in this environment (objects in ancestor
environments are ingored).
*/
object_iterator begin_local_objects() const { return object_iterator(m_this.lock(), 0, true); }
/**
\brief Return an iterator to the end of the sequence of
objects stored in this environment (objects in ancestor
environments are ingored).
*/
object_iterator end_local_objects() const { return object_iterator(m_this.lock(), get_num_objects(true), true); }
// =======================================
/**
\brief Register an environment extension. Every environment
object will contain this extension. The funciton mk creates a
new instance of the extension. The extension object can be
retrieved using the token (unsigned integer) returned by this
method.
\remark The extension objects are created on demand.
\see get_extension
*/
typedef std::unique_ptr<environment_extension> (*mk_extension)();
static unsigned register_extension(mk_extension mk);
/**
\brief Retrieve the extension associated with the token \c extid.
The token is the value returned by \c register_extension.
*/
template<typename Ext>
Ext const & get_extension(unsigned extid) const {
environment_extension const & ext = get_extension_core(extid);
lean_assert(dynamic_cast<Ext const *>(&ext) != nullptr);
return static_cast<Ext const &>(ext);
}
template<typename Ext>
Ext & get_extension(unsigned extid) {
environment_extension & ext = get_extension_core(extid);
lean_assert(dynamic_cast<Ext*>(&ext) != nullptr);
return static_cast<Ext&>(ext);
}
void export_objects(std::string const & fname);
bool import(std::string const & fname, io_state const & ios);
void load(std::string const & fname, io_state const & ios);
/** \brief Return true iff module \c n has already been imported */
bool imported(std::string const & n) const;
/**
\brief When trusted_imported flag is true, the environment will
not type check imported modules.
*/
void set_trusted_imported(bool flag);
/**
\brief Execute function \c fn. Any object created by \c fn
is not exported by the environment.
*/
void auxiliary_section(std::function<void()> fn);
};
/**
\brief Frontend can store data in environment extensions.
Each extension is associated with a unique token/id.
This token allows the frontend to retrieve/store an extension object
in the environment
*/
class environment_extension {
friend class environment_cell;
environment_cell * m_env;
unsigned m_extid; // extension id
environment_extension const * get_parent_core() const;
public:
environment_extension();
virtual ~environment_extension();
/**
\brief Return a constant reference for a parent extension,
and a nullptr if there is no parent/ancestor, or if the
parent/ancestor has an extension.
*/
template<typename Ext> Ext const * get_parent() const {
environment_extension const * ext = get_parent_core();
lean_assert(!ext || dynamic_cast<Ext const *>(ext) != nullptr);
return static_cast<Ext const *>(ext);
}
};
/**
\brief Reference to environment
*/
class environment {
friend class ro_environment;
friend class environment_cell;
friend class read_write_shared_environment;
std::shared_ptr<environment_cell> m_ptr;
environment(std::shared_ptr<environment_cell> const & parent, bool);
environment(std::shared_ptr<environment_cell> const & ptr);
public:
environment();
environment_cell * operator->() const { return m_ptr.get(); }
environment_cell & operator*() const { return *(m_ptr.get()); }
};
/**
\brief Read-only reference to environment.
*/
class ro_environment {
friend class environment_cell;
friend class read_only_shared_environment;
std::shared_ptr<environment_cell const> m_ptr;
ro_environment(std::shared_ptr<environment_cell const> const & p):m_ptr(p) {}
friend int push_environment(lua_State * L, ro_environment const & env);
environment cast_to_environment() const { return environment(std::const_pointer_cast<environment_cell>(m_ptr)); }
public:
typedef std::weak_ptr<environment_cell const> weak_ref;
ro_environment(environment const & env);
ro_environment(weak_ref const & env);
explicit operator weak_ref() const { return weak_ref(m_ptr); }
weak_ref to_weak_ref() const { return weak_ref(m_ptr); }
environment_cell const * operator->() const { return m_ptr.get(); }
environment_cell const & operator*() const { return *(m_ptr.get()); }
};
/** \brief Return true iff the given object marks the begin of the of a sequence of imported objects. */
bool is_begin_import(object const & obj);
/** \brief Return true iff the given object marks the begin of the of a sequence of builtin imported objects. */
bool is_begin_builtin_import(object const & obj);
/** \brief Return true iff the given object marks the end of the of a sequence of imported objects. */
bool is_end_import(object const & obj);
/**
\brief Return the module imported by the given import object.
Return none if \c obj is not an import object.
*/
optional<std::string> get_imported_module(object const & obj);
/**
\brief Return true iff \c obj is a set_opaque command mark.
*/
bool is_set_opaque(object const & obj);
/**
\brief Return the identifier of a set_opaque command.
\pre is_set_opaque(obj)
*/
name const & get_set_opaque_id(object const & obj);
/**
\brief Return the flag of a set_opaque command.
\pre is_set_opaque(obj)
*/
bool get_set_opaque_flag(object const & obj);
}