lean4-htt/src/library/local_context.h

128 lines
5.5 KiB
C++

/*
Copyright (c) 2016 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/name_map.h"
#include "util/name_set.h"
#include "kernel/expr.h"
namespace lean {
class local_decl {
public:
struct cell {
/*
<name> : <type> := <value>
m_pp_name is used for interacting with the user.
It may not be not unique.
*/
name m_name; /* this one is unique */
name m_pp_name;
expr m_type;
optional<expr> m_value;
binder_info m_bi;
unsigned m_idx;
MK_LEAN_RC(); // Declare m_rc counter
void dealloc();
cell(unsigned idx, name const & n, name const & pp_n, expr const & t, optional<expr> const & v,
binder_info const & bi);
};
private:
cell * m_ptr;
friend class local_context;
friend void initialize_local_context();
local_decl(unsigned idx, name const & n, name const & pp_n, expr const & t, optional<expr> const & v, binder_info const & bi);
public:
local_decl();
local_decl(local_decl const & s):m_ptr(s.m_ptr) { if (m_ptr) m_ptr->inc_ref(); }
local_decl(local_decl && s):m_ptr(s.m_ptr) { s.m_ptr = nullptr; }
~local_decl() { if (m_ptr) m_ptr->dec_ref(); }
local_decl & operator=(local_decl const & s) { LEAN_COPY_REF(s); }
local_decl & operator=(local_decl && s) { LEAN_MOVE_REF(s); }
friend bool is_eqp(local_decl const & a, local_decl const & b) { return a.m_ptr == b.m_ptr; }
name const & get_name() const { return m_ptr->m_name; }
name const & get_pp_name() const { return m_ptr->m_pp_name; }
expr const & get_type() const { return m_ptr->m_type; }
optional<expr> const & get_value() const { return m_ptr->m_value; }
binder_info const & get_info() const { return m_ptr->m_bi; }
expr mk_ref() const;
unsigned get_idx() const { return m_ptr->m_idx; }
};
bool is_local_decl_ref(expr const & e);
bool depends_on(expr const & e, unsigned num, expr const * locals);
bool depends_on(local_decl const & d, unsigned num, expr const * locals);
bool depends_on(expr const & e, buffer<expr> const & locals);
bool depends_on(local_decl const & d, buffer<expr> const & locals);
class local_context {
typedef rb_map<unsigned, local_decl, unsigned_cmp> idx2local_decl;
unsigned m_next_idx;
name_map<local_decl> m_name2local_decl;
idx2local_decl m_idx2local_decl;
/*
A local context can optionally have a set of frozen declarations.
Moreover, type class resolution can be restricted to use only frozen local
declarations. When this restriction is use, we can cache type class instances
more efficiently.
*/
name_set m_frozen_decls; /* declarations that have been frozen */
friend class type_context;
local_context remove(buffer<expr> const & locals) const;
expr mk_local_decl(name const & n, name const & ppn, expr const & type,
optional<expr> const & value, binder_info const & bi);
public:
local_context():m_next_idx(0) {}
expr mk_local_decl(expr const & type, binder_info const & bi = binder_info());
expr mk_local_decl(expr const & type, expr const & value);
expr mk_local_decl(name const & ppn, expr const & type, binder_info const & bi = binder_info());
expr mk_local_decl(name const & ppn, expr const & type, expr const & value);
/** \brief Return the local declarations for the given reference.
\pre is_local_decl_ref(e) */
optional<local_decl> get_local_decl(expr const & e) const;
optional<local_decl> get_local_decl(name const & n) const;
/** \brief Traverse local declarations based on the order they were created */
void for_each(std::function<void(local_decl const &)> const & fn) const;
optional<local_decl> find_if(std::function<bool(local_decl const &)> const & pred) const; // NOLINT
optional<local_decl> back_find_if(std::function<bool(local_decl const &)> const & pred) const; // NOLINT
/** \brief Return the most recently added local_decl \c d s.t. d.get_pp_name() == n
\remark This method is used to implement tactics such as 'revert'. */
optional<local_decl> get_local_decl_from_user_name(name const & n) const;
/** \brief Execute fn for each local declaration created after \c d. */
void for_each_after(local_decl const & d, std::function<void(local_decl const &)> const & fn) const;
void freeze(name const & n);
bool is_frozen(name const & n) const { return m_frozen_decls.contains(n); }
/** \brief Return true iff all locals in this context are in the set \c ls. */
bool is_subset_of(name_set const & ls) const;
/** \brief Return true iff all locals in this context are also in \c ctx. */
bool is_subset_of(local_context const & ctx) const;
void pop_local_decl();
/** \brief We say a local context is well-formed iff all local declarations only
contain local_decl references that were defined before them.
\remark This method is for debugging purposes. */
bool well_formed() const;
/** \brief Return true iff \c e is well-formed with respect to this local context.
That is, all local_decl references in \c e are defined in this context.
\remark This method is for debugging purposes. */
bool well_formed(expr const & e) const;
};
void initialize_local_context();
void finalize_local_context();
}