lean2/src/kernel/declaration.cpp
Leonardo de Moura e635d9be9f refactor(kernel): rename get_weight to get_height at declaration
Motivation:
- It is the standard name for the concept: declaration height
- Avoid confusion with the expression weight
2015-06-30 12:59:10 -07:00

106 lines
4.8 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
*/
#include "kernel/declaration.h"
#include "kernel/environment.h"
#include "kernel/for_each_fn.h"
namespace lean {
struct declaration::cell {
MK_LEAN_RC();
name m_name;
level_param_names m_params;
expr m_type;
bool m_theorem;
optional<expr> m_value; // if none, then declaration is actually a postulate
unsigned m_height; // definitional height
// The following field affects the convertability checker.
// Let f be this definition, then if the following field is true,
// then whenever we are checking whether
// (f a) is convertible to (f b)
// we will first check whether a is convertible to b.
// If the test fails, then we perform the full check.
bool m_use_conv_opt;
void dealloc() { delete this; }
cell(name const & n, level_param_names const & params, expr const & t, bool is_axiom):
m_rc(1), m_name(n), m_params(params), m_type(t), m_theorem(is_axiom),
m_height(0), m_use_conv_opt(false) {}
cell(name const & n, level_param_names const & params, expr const & t, bool is_thm, expr const & v,
unsigned h, bool use_conv_opt):
m_rc(1), m_name(n), m_params(params), m_type(t), m_theorem(is_thm),
m_value(v), m_height(h), m_use_conv_opt(use_conv_opt) {}
};
static declaration * g_dummy = nullptr;
declaration::declaration():declaration(*g_dummy) {}
declaration::declaration(cell * ptr):m_ptr(ptr) {}
declaration::declaration(declaration const & s):m_ptr(s.m_ptr) { if (m_ptr) m_ptr->inc_ref(); }
declaration::declaration(declaration && s):m_ptr(s.m_ptr) { s.m_ptr = nullptr; }
declaration::~declaration() { if (m_ptr) m_ptr->dec_ref(); }
declaration & declaration::operator=(declaration const & s) { LEAN_COPY_REF(s); }
declaration & declaration::operator=(declaration && s) { LEAN_MOVE_REF(s); }
bool declaration::is_definition() const { return static_cast<bool>(m_ptr->m_value); }
bool declaration::is_constant_assumption() const { return !is_definition(); }
bool declaration::is_axiom() const { return is_constant_assumption() && m_ptr->m_theorem; }
bool declaration::is_theorem() const { return is_definition() && m_ptr->m_theorem; }
name const & declaration::get_name() const { return m_ptr->m_name; }
level_param_names const & declaration::get_univ_params() const { return m_ptr->m_params; }
unsigned declaration::get_num_univ_params() const { return length(get_univ_params()); }
expr const & declaration::get_type() const { return m_ptr->m_type; }
expr const & declaration::get_value() const { lean_assert(is_definition()); return *(m_ptr->m_value); }
unsigned declaration::get_height() const { return m_ptr->m_height; }
bool declaration::use_conv_opt() const { return m_ptr->m_use_conv_opt; }
declaration mk_definition(name const & n, level_param_names const & params, expr const & t, expr const & v,
unsigned height, bool use_conv_opt) {
return declaration(new declaration::cell(n, params, t, false, v, height, use_conv_opt));
}
static unsigned get_max_height(environment const & env, expr const & v) {
unsigned h = 0;
for_each(v, [&](expr const & e, unsigned) {
if (is_constant(e)) {
auto d = env.find(const_name(e));
if (d && d->get_height() > h)
h = d->get_height();
}
return true;
});
return h;
}
declaration mk_definition(environment const & env, name const & n, level_param_names const & params, expr const & t,
expr const & v, bool use_conv_opt) {
unsigned h = get_max_height(env, v);
return mk_definition(n, params, t, v, h+1, use_conv_opt);
}
declaration mk_theorem(environment const & env, name const & n, level_param_names const & params, expr const & t, expr const & v) {
unsigned h = get_max_height(env, v);
return declaration(new declaration::cell(n, params, t, true, v, h+1, true));
}
declaration mk_theorem(name const & n, level_param_names const & params, expr const & t, expr const & v, unsigned height) {
return declaration(new declaration::cell(n, params, t, true, v, height, true));
}
declaration mk_axiom(name const & n, level_param_names const & params, expr const & t) {
return declaration(new declaration::cell(n, params, t, true));
}
declaration mk_constant_assumption(name const & n, level_param_names const & params, expr const & t) {
return declaration(new declaration::cell(n, params, t, false));
}
void initialize_declaration() {
g_dummy = new declaration(mk_axiom(name(), level_param_names(), expr()));
}
void finalize_declaration() {
delete g_dummy;
}
}