lean2/src/kernel/metavar.h
Leonardo de Moura 13fe28dd1c perf(library/unifier): delay the instantiation of metavariables occurring in the types of local constants
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
2014-07-23 14:31:30 -07:00

94 lines
4.9 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 <utility>
#include "util/rb_map.h"
#include "util/optional.h"
#include "util/name_set.h"
#include "kernel/expr.h"
#include "kernel/justification.h"
namespace lean {
class substitution {
typedef rb_map<name, expr, name_quick_cmp> expr_map;
typedef rb_map<name, level, name_quick_cmp> level_map;
typedef rb_map<name, justification, name_quick_cmp> jst_map;
expr_map m_expr_subst;
level_map m_level_subst;
jst_map m_expr_jsts;
jst_map m_level_jsts;
friend class instantiate_metavars_fn;
std::pair<level, justification> instantiate_metavars(level const & l, bool use_jst);
expr instantiate_metavars_wo_jst(expr const & e, bool inst_local_types);
std::pair<expr, justification> instantiate_metavars_core(expr const & e, bool inst_local_types);
bool occurs_expr_core(name const & m, expr const & e, name_set & visited) const;
public:
substitution();
typedef optional<std::pair<expr, justification>> opt_expr_jst;
typedef optional<std::pair<level, justification>> opt_level_jst;
bool is_expr_assigned(name const & m) const;
opt_expr_jst get_expr_assignment(name const & m) const;
bool is_level_assigned(name const & m) const;
opt_level_jst get_level_assignment(name const & m) const;
optional<expr> get_expr(name const & m) const;
optional<level> get_level(name const & m) const;
justification get_expr_jst(name const & m) const { if (auto it = m_expr_jsts.find(m)) return *it; else return justification(); }
justification get_level_jst(name const & m) const { if (auto it = m_level_jsts.find(m)) return *it; else return justification(); }
void assign(name const & m, expr const & t, justification const & j);
void assign(name const & m, expr const & t) { assign(m, t, justification()); }
void assign(expr const & m, expr const & t, justification const & j) { assign(mlocal_name(m), t, j); }
void assign(expr const & m, expr const & t) { assign(m, t, justification()); }
void assign(name const & m, level const & t, justification const & j);
void assign(name const & m, level const & t) { assign(m, t, justification ()); }
void assign(level const & m, level const & t, justification const & j) { assign(meta_id(m), t, j); }
void assign(level const & m, level const & t) { assign(m, t, justification ()); }
std::pair<level, justification> instantiate_metavars(level const & l) { return instantiate_metavars(l, true); }
/** \brief Instantiate metavariables occurring in \c e, by default this method does not visit the types of local constants.
For substituting the metavariables occurring in local constants, use instantiate_metavars_all.
*/
std::pair<expr, justification> instantiate_metavars(expr const & e) { return instantiate_metavars_core(e, false); }
/** \brief \c see instantiate_metavars */
std::pair<expr, justification> instantiate_metavars_all(expr const & e) { return instantiate_metavars_core(e, true); }
/** \brief Similar to \c instantiate_metavars, but does not compute a justification for the substitutions. */
expr instantiate(expr const & e) { return instantiate_metavars_wo_jst(e, false); }
/** \brief Similar to instantiate, but also substitute metavariables occurring in the types of local constansts */
expr instantiate_all(expr const & e) { return instantiate_metavars_wo_jst(e, true); }
void forget_justifications() { m_expr_jsts = jst_map(); m_level_jsts = jst_map(); }
template<typename F>
void for_each_expr(F && fn) const {
for_each(m_expr_subst, [=](name const & n, expr const & e) { fn(n, e, get_expr_jst(n)); });
}
template<typename F>
void for_each_level(F && fn) const {
for_each(m_level_subst, [=](name const & n, level const & l) { fn(n, l, get_level_jst(n)); });
}
bool is_assigned(expr const & m) const { lean_assert(is_metavar(m)); return is_expr_assigned(mlocal_name(m)); }
opt_expr_jst get_assignment(expr const & m) const { lean_assert(is_metavar(m)); return get_expr_assignment(mlocal_name(m)); }
optional<expr> get_expr(expr const & m) const { lean_assert(is_metavar(m)); return get_expr(mlocal_name(m)); }
bool is_assigned(level const & m) const { lean_assert(is_meta(m)); return is_level_assigned(meta_id(m)); }
opt_level_jst get_assignment(level const & m) const { lean_assert(is_meta(m)); return get_level_assignment(meta_id(m)); }
optional<level> get_level(level const & m) const { lean_assert(is_meta(m)); return get_level(meta_id(m)); }
/** \brief Return true iff the metavariable \c m occurrs (directly or indirectly) in \c e. */
bool occurs_expr(name const & m, expr const & e) const;
bool occurs(expr const & m, expr const & e) const { lean_assert(is_metavar(m)); return occurs_expr(mlocal_name(m), e); }
};
}