lean4-htt/src/library/aux_definition.cpp

194 lines
8 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
*/
#include <algorithm>
#include "kernel/type_checker.h"
#include "kernel/replace_fn.h"
#include "library/locals.h"
#include "library/module.h"
#include "library/trace.h"
#include "library/aux_definition.h"
#include "library/unfold_macros.h"
namespace lean {
struct mk_aux_definition_fn {
type_context & m_ctx;
name m_prefix;
unsigned m_next_idx;
name_set m_found_univ_params;
name_map<level> m_univ_meta_to_param;
name_map<level> m_univ_meta_to_param_inv;
name_set m_found_local;
name_map<expr> m_meta_to_param;
name_map<expr> m_meta_to_param_inv;
buffer<name> m_level_params;
buffer<expr> m_params;
mk_aux_definition_fn(type_context & ctx):
m_ctx(ctx),
m_prefix("_aux_param"),
m_next_idx(0) {}
level collect(level const & l) {
return replace(l, [&](level const & l) {
if (is_meta(l)) {
name const & id = meta_id(l);
if (auto r = m_univ_meta_to_param.find(id)) {
return some_level(*r);
} else {
name n = m_prefix.append_after(m_next_idx);
m_next_idx++;
level new_r = mk_param_univ(n);
m_univ_meta_to_param.insert(id, new_r);
m_univ_meta_to_param_inv.insert(n, l);
m_level_params.push_back(n);
return some_level(new_r);
}
} else if (is_param(l)) {
name const & id = param_id(l);
if (!m_found_univ_params.contains(id)) {
m_found_univ_params.insert(id);
m_level_params.push_back(id);
}
}
return none_level();
});
}
levels collect(levels const & ls) {
bool modified = false;
buffer<level> r;
for (level const & l : ls) {
level new_l = collect(l);
if (new_l != l) modified = true;
r.push_back(new_l);
}
if (!modified)
return ls;
else
return to_list(r);
}
expr collect(expr const & e) {
return replace(e, [&](expr const & e, unsigned) {
if (is_metavar(e)) {
name const & id = mlocal_name(e);
if (auto r = m_meta_to_param.find(id)) {
return some_expr(*r);
} else {
expr type = m_ctx.infer(e);
expr x = m_ctx.push_local("_x", type);
m_meta_to_param.insert(id, x);
m_meta_to_param_inv.insert(mlocal_name(x), e);
m_params.push_back(x);
return some_expr(x);
}
} else if (is_local(e)) {
name const & id = mlocal_name(e);
if (!m_found_local.contains(id)) {
m_found_local.insert(id);
m_params.push_back(e);
}
} else if (is_sort(e)) {
return some_expr(update_sort(e, collect(sort_level(e))));
} else if (is_constant(e)) {
return some_expr(update_constant(e, collect(const_levels(e))));
}
return none_expr();
});
}
/* Collect (and sort) dependencies of collected parameters */
void collect_and_normalize_dependencies(buffer<expr> & norm_params) {
name_map<expr> new_types;
for (unsigned i = 0; i < m_params.size(); i++) {
expr x = m_params[i];
expr new_type = collect(m_ctx.instantiate_mvars(m_ctx.infer(x)));
new_types.insert(mlocal_name(x), new_type);
}
local_context const & lctx = m_ctx.lctx();
std::sort(m_params.begin(), m_params.end(), [&](expr const & l1, expr const & l2) {
return lctx.get_local_decl(l1)->get_idx() < lctx.get_local_decl(l2)->get_idx();
});
for (unsigned i = 0; i < m_params.size(); i++) {
expr x = m_params[i];
expr type = *new_types.find(mlocal_name(x));
expr new_type = replace_locals(type, i, m_params.data(), norm_params.data());
expr new_param = m_ctx.push_local(local_pp_name(x), new_type, local_info(x));
norm_params.push_back(new_param);
}
}
pair<environment, expr> operator()(name const & c, expr const & type, expr const & value, bool is_lemma, optional<bool> const & is_meta) {
lean_assert(!is_lemma || is_meta);
lean_assert(!is_lemma || *is_meta == false);
expr new_type = collect(m_ctx.instantiate_mvars(type));
expr new_value = collect(m_ctx.instantiate_mvars(value));
environment const & env = m_ctx.env();
buffer<expr> norm_params;
collect_and_normalize_dependencies(norm_params);
new_type = replace_locals(new_type, m_params, norm_params);
new_value = replace_locals(new_value, m_params, norm_params);
expr def_type = m_ctx.mk_pi(norm_params, new_type);
expr def_value = m_ctx.mk_lambda(norm_params, new_value);
bool untrusted = false;
if (is_meta)
untrusted = *is_meta;
else
untrusted = use_untrusted(env, def_type) || use_untrusted(env, def_value);
if (!untrusted) {
def_type = unfold_untrusted_macros(env, def_type);
def_value = unfold_untrusted_macros(env, def_value);
}
declaration d;
if (is_lemma) {
d = mk_theorem(c, to_list(m_level_params), def_type, def_value);
} else {
bool use_self_opt = true;
d = mk_definition(env, c, to_list(m_level_params), def_type, def_value, use_self_opt, !untrusted);
}
environment new_env = module::add(env, check(env, d, true));
buffer<level> ls;
for (name const & n : m_level_params) {
if (level const * l = m_univ_meta_to_param_inv.find(n))
ls.push_back(*l);
else
ls.push_back(mk_param_univ(n));
}
buffer<expr> ps;
for (expr const & x : m_params) {
if (expr const * m = m_meta_to_param_inv.find(mlocal_name(x)))
ps.push_back(*m);
else
ps.push_back(x);
}
expr r = mk_app(mk_constant(c, to_list(ls)), ps);
return mk_pair(new_env, r);
}
};
pair<environment, expr> mk_aux_definition(environment const & env, metavar_context const & mctx, local_context const & lctx,
name const & c, expr const & type, expr const & value, optional<bool> const & is_meta) {
type_context ctx(env, options(), mctx, lctx, transparency_mode::All);
bool is_lemma = false;
return mk_aux_definition_fn(ctx)(c, type, value, is_lemma, is_meta);
}
pair<environment, expr> mk_aux_definition(environment const & env, metavar_context const & mctx, local_context const & lctx,
name const & c, expr const & value, optional<bool> const & is_meta) {
type_context ctx(env, options(), mctx, lctx, transparency_mode::All);
expr type = ctx.infer(value);
bool is_lemma = false;
return mk_aux_definition_fn(ctx)(c, type, value, is_lemma, is_meta);
}
pair<environment, expr> mk_aux_lemma(environment const & env, metavar_context const & mctx, local_context const & lctx,
name const & c, expr const & type, expr const & value) {
type_context ctx(env, options(), mctx, lctx, transparency_mode::All);
bool is_lemma = true;
optional<bool> is_meta(false);
return mk_aux_definition_fn(ctx)(c, type, value, is_lemma, is_meta);
}
}