1114 lines
35 KiB
C++
1114 lines
35 KiB
C++
/*
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Copyright (c) 2014 Microsoft Corporation. All rights reserved.
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Released under Apache 2.0 license as described in the file LICENSE.
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Author: Leonardo de Moura
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*/
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#include <algorithm>
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#include "util/fresh_name.h"
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#include "kernel/find_fn.h"
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#include "kernel/free_vars.h"
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#include "kernel/instantiate.h"
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#include "kernel/error_msgs.h"
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#include "kernel/type_checker.h"
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#include "kernel/abstract.h"
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#include "kernel/abstract_type_context.h"
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#include "kernel/inductive/inductive.h"
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#include "library/locals.h"
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#include "library/util.h"
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#include "library/annotation.h"
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#include "library/constants.h"
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#include "library/unfold_macros.h"
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#include "library/pp_options.h"
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#include "library/projection.h"
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#include "library/replace_visitor.h"
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#include "library/type_context.h"
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namespace lean {
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/** \brief Return the "arity" of the given type. The arity is the number of nested pi-expressions. */
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unsigned get_arity(expr type) {
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unsigned r = 0;
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while (is_pi(type)) {
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type = binding_body(type);
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r++;
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}
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return r;
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}
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bool is_internal_name(name const & n) {
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name it = n;
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while (!it.is_anonymous()) {
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if (!it.is_anonymous() && it.is_string() && it.get_string() && it.get_string()[0] == '_')
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return true;
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it = it.get_prefix();
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}
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return false;
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}
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optional<expr> is_optional_param(expr const & e) {
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if (is_app_of(e, get_opt_param_name(), 2)) {
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return some_expr(app_arg(e));
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} else {
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return none_expr();
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}
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}
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optional<expr_pair> is_auto_param(expr const & e) {
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if (is_app_of(e, get_auto_param_name(), 2)) {
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return optional<expr_pair>(app_arg(app_fn(e)), app_arg(e));
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} else {
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return optional<expr_pair>();
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}
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}
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level get_level(abstract_type_context & ctx, expr const & A) {
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expr S = ctx.relaxed_whnf(ctx.infer(A));
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if (!is_sort(S))
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throw exception("invalid expression, sort expected");
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return sort_level(S);
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}
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name mk_fresh_lp_name(level_param_names const & lp_names) {
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name l("l");
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int i = 1;
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while (std::find(lp_names.begin(), lp_names.end(), l) != lp_names.end()) {
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l = name("l").append_after(i);
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i++;
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}
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return l;
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}
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bool occurs(expr const & n, expr const & m) {
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return static_cast<bool>(find(m, [&](expr const & e, unsigned) { return n == e; }));
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}
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bool occurs(name const & n, expr const & m) {
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return static_cast<bool>(find(m, [&](expr const & e, unsigned) { return is_constant(e) && const_name(e) == n; }));
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}
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bool is_app_of(expr const & t, name const & f_name) {
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expr const & fn = get_app_fn(t);
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return is_constant(fn) && const_name(fn) == f_name;
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}
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bool is_app_of(expr const & t, name const & f_name, unsigned nargs) {
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expr const & fn = get_app_fn(t);
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return is_constant(fn) && const_name(fn) == f_name && get_app_num_args(t) == nargs;
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}
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expr consume_opt_param(expr const & type) {
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if (is_app_of(type, get_opt_param_name(), 2)) {
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/* make sure (opt_param 'a value) does not affect results */
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return app_arg(app_fn(type));
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} else {
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return type;
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}
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}
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optional<expr> unfold_term(environment const & env, expr const & e) {
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expr const & f = get_app_fn(e);
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if (!is_constant(f))
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return none_expr();
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auto decl = env.find(const_name(f));
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if (!decl || !decl->is_definition())
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return none_expr();
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expr d = instantiate_value_univ_params(*decl, const_levels(f));
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buffer<expr> args;
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get_app_rev_args(e, args);
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return some_expr(apply_beta(d, args.size(), args.data()));
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}
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optional<expr> unfold_app(environment const & env, expr const & e) {
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if (!is_app(e))
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return none_expr();
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return unfold_term(env, e);
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}
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optional<level> dec_level(level const & l) {
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switch (kind(l)) {
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case level_kind::Zero: case level_kind::Param: case level_kind::Meta:
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return none_level();
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case level_kind::Succ:
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return some_level(succ_of(l));
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case level_kind::Max:
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if (auto lhs = dec_level(max_lhs(l))) {
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if (auto rhs = dec_level(max_rhs(l))) {
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return some_level(mk_max(*lhs, *rhs));
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}}
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return none_level();
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case level_kind::IMax:
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// Remark: the following mk_max is not a typo. The following
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// assertion justifies it.
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if (auto lhs = dec_level(imax_lhs(l))) {
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if (auto rhs = dec_level(imax_rhs(l))) {
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return some_level(mk_max(*lhs, *rhs));
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}}
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return none_level();
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}
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lean_unreachable(); // LCOV_EXCL_LINE
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}
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/** \brief Return true if environment has a constructor named \c c that returns
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an element of the inductive datatype named \c I, and \c c must have \c nparams parameters. */
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bool has_constructor(environment const & env, name const & c, name const & I, unsigned nparams) {
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auto d = env.find(c);
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if (!d || d->is_definition())
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return false;
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expr type = d->get_type();
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unsigned i = 0;
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while (is_pi(type)) {
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i++;
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type = binding_body(type);
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}
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if (i != nparams)
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return false;
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type = get_app_fn(type);
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return is_constant(type) && const_name(type) == I;
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}
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bool has_punit_decls(environment const & env) {
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return has_constructor(env, get_punit_star_name(), get_punit_name(), 0);
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}
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bool has_eq_decls(environment const & env) {
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return has_constructor(env, get_eq_refl_name(), get_eq_name(), 2);
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}
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bool has_heq_decls(environment const & env) {
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return has_constructor(env, get_heq_refl_name(), get_heq_name(), 2);
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}
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bool has_pprod_decls(environment const & env) {
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return has_constructor(env, get_pprod_mk_name(), get_pprod_name(), 4);
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}
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bool has_and_decls(environment const & env) {
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return has_constructor(env, get_and_intro_name(), get_and_name(), 4);
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}
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/* n is considered to be recursive if it is an inductive datatype and
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1) It has a constructor that takes n as an argument
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2) It is part of a mutually recursive declaration, and some constructor
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of an inductive datatype takes another inductive datatype from the
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same declaration as an argument. */
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bool is_recursive_datatype(environment const & env, name const & n) {
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optional<inductive::inductive_decl> decl = inductive::is_inductive_decl(env, n);
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if (!decl) return false;
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for (inductive::intro_rule const & intro : decl->m_intro_rules) {
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expr type = inductive::intro_rule_type(intro);
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while (is_pi(type)) {
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if (find(binding_domain(type), [&](expr const & e, unsigned) {
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if (is_constant(e)) {
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name const & c = const_name(e);
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if (decl->m_name == c) return true;
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}
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return false;
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})) {
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return true;
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}
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type = binding_body(type);
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}
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}
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return false;
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}
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bool is_reflexive_datatype(abstract_type_context & tc, name const & n) {
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environment const & env = tc.env();
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optional<inductive::inductive_decl> decl = inductive::is_inductive_decl(env, n);
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if (!decl) return false;
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for (inductive::intro_rule const & intro : decl->m_intro_rules) {
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expr type = inductive::intro_rule_type(intro);
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while (is_pi(type)) {
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expr arg = tc.whnf(binding_domain(type));
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if (is_pi(arg) && find(arg, [&](expr const & e, unsigned) { return is_constant(e) && const_name(e) == n; })) {
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return true;
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}
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expr local = mk_local(mk_fresh_name(), binding_domain(type));
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type = instantiate(binding_body(type), local);
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}
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}
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return false;
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}
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level get_datatype_level(environment const & env, expr const & ind_type) {
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expr it = ind_type;
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while (is_pi(it))
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it = binding_body(it);
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if (is_sort(it)) {
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return sort_level(it);
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} else {
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type_checker ctx(env);
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buffer<expr> telescope;
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expr it = ctx.whnf(to_telescope(ctx, ind_type, telescope));
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if (is_sort(it)) {
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return sort_level(it);
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} else {
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throw exception("invalid inductive datatype type");
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}
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}
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}
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expr update_result_sort(expr t, level const & l) {
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if (is_pi(t)) {
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return update_binding(t, binding_domain(t), update_result_sort(binding_body(t), l));
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} else if (is_sort(t)) {
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return update_sort(t, l);
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} else {
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lean_unreachable();
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}
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}
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bool is_inductive_predicate(environment const & env, name const & n) {
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if (!inductive::is_inductive_decl(env, n))
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return false; // n is not inductive datatype
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return is_zero(get_datatype_level(env, env.get(n).get_type()));
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}
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bool can_elim_to_type(environment const & env, name const & n) {
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if (!inductive::is_inductive_decl(env, n))
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return false; // n is not inductive datatype
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declaration ind_decl = env.get(n);
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declaration rec_decl = env.get(inductive::get_elim_name(n));
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return rec_decl.get_num_univ_params() > ind_decl.get_num_univ_params();
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}
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void get_intro_rule_names(environment const & env, name const & n, buffer<name> & result) {
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if (auto decl = inductive::is_inductive_decl(env, n)) {
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for (inductive::intro_rule const & ir : decl->m_intro_rules) {
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result.push_back(inductive::intro_rule_name(ir));
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}
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}
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}
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optional<name> is_constructor_app(environment const & env, expr const & e) {
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expr const & fn = get_app_fn(e);
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if (is_constant(fn))
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if (auto I = inductive::is_intro_rule(env, const_name(fn)))
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return optional<name>(const_name(fn));
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return optional<name>();
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}
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optional<name> is_constructor_app_ext(environment const & env, expr const & e) {
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if (auto r = is_constructor_app(env, e))
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return r;
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expr const & f = get_app_fn(e);
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if (!is_constant(f))
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return optional<name>();
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auto decl = env.find(const_name(f));
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if (!decl || !decl->is_definition())
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return optional<name>();
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expr const * it = &decl->get_value();
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while (is_lambda(*it))
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it = &binding_body(*it);
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return is_constructor_app_ext(env, *it);
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}
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static bool is_irrelevant_field_type(type_checker & tc, expr const & ftype) {
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if (tc.is_prop(ftype)) return true;
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buffer<expr> tele;
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expr n_ftype = to_telescope(tc, ftype, tele);
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return is_sort(n_ftype) || tc.is_prop(n_ftype);
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}
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void get_constructor_relevant_fields(environment const & env, name const & n, buffer<bool> & result) {
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lean_assert(inductive::is_intro_rule(env, n));
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expr type = env.get(n).get_type();
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name I_name = *inductive::is_intro_rule(env, n);
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unsigned nparams = *inductive::get_num_params(env, I_name);
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buffer<expr> telescope;
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type_checker tc(env);
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to_telescope(tc, type, telescope);
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lean_assert(telescope.size() >= nparams);
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for (unsigned i = nparams; i < telescope.size(); i++) {
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result.push_back(!is_irrelevant_field_type(tc, mlocal_type(telescope[i])));
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}
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}
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unsigned get_constructor_idx(environment const & env, name const & n) {
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lean_assert(inductive::is_intro_rule(env, n));
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name I_name = *inductive::is_intro_rule(env, n);
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buffer<name> cnames;
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get_intro_rule_names(env, I_name, cnames);
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unsigned r = 0;
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for (name const & cname : cnames) {
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if (cname == n)
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return r;
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r++;
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}
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lean_unreachable();
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}
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unsigned get_num_inductive_hypotheses_for(environment const & env, name const & n, buffer<bool> & rec_mask) {
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lean_assert(inductive::is_intro_rule(env, n));
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lean_assert(rec_mask.empty());
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name I_name = *inductive::is_intro_rule(env, n);
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inductive::inductive_decl decl = *inductive::is_inductive_decl(env, I_name);
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type_context tc(env);
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type_context::tmp_locals locals(tc);
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expr type = tc.whnf(env.get(n).get_type());
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unsigned r = 0;
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while (is_pi(type)) {
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auto dom = tc.whnf(binding_domain(type));
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while (is_pi(dom)) {
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dom = tc.whnf(instantiate(binding_body(dom), locals.push_local_from_binding(dom)));
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}
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auto fn = get_app_fn(dom);
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if (is_constant(fn) && const_name(fn) == decl.m_name) {
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rec_mask.push_back(true);
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r++;
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} else {
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rec_mask.push_back(false);
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}
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type = tc.whnf(instantiate(binding_body(type), locals.push_local_from_binding(type)));
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}
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return r;
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}
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unsigned get_num_inductive_hypotheses_for(environment const & env, name const & n) {
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buffer<bool> rec_mask;
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return get_num_inductive_hypotheses_for(env, n, rec_mask);
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}
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void get_constructor_rec_arg_mask(environment const & env, name const & n, buffer<bool> & rec_mask) {
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get_num_inductive_hypotheses_for(env, n, rec_mask);
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}
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expr instantiate_univ_param (expr const & e, name const & p, level const & l) {
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return instantiate_univ_params(e, to_list(p), to_list(l));
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}
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unsigned get_expect_num_args(abstract_type_context & ctx, expr e) {
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push_local_fn push_local(ctx);
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unsigned r = 0;
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while (true) {
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e = ctx.whnf(e);
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if (!is_pi(e))
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return r;
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// TODO(Leo): try to avoid the following instantiate.
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expr local = push_local(binding_name(e), binding_domain(e), binding_info(e));
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e = instantiate(binding_body(e), local);
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r++;
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}
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}
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expr to_telescope(bool pi, expr e, buffer<expr> & telescope,
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optional<binder_info> const & binfo) {
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while ((pi && is_pi(e)) || (!pi && is_lambda(e))) {
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expr local;
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if (binfo)
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local = mk_local(mk_fresh_name(), binding_name(e), binding_domain(e), *binfo);
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else
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local = mk_local(mk_fresh_name(), binding_name(e), binding_domain(e), binding_info(e));
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telescope.push_back(local);
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e = instantiate(binding_body(e), local);
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}
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return e;
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}
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expr to_telescope(expr const & type, buffer<expr> & telescope, optional<binder_info> const & binfo) {
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return to_telescope(true, type, telescope, binfo);
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}
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expr fun_to_telescope(expr const & e, buffer<expr> & telescope,
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optional<binder_info> const & binfo) {
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return to_telescope(false, e, telescope, binfo);
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}
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expr to_telescope(type_checker & ctx, expr type, buffer<expr> & telescope, optional<binder_info> const & binfo) {
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expr new_type = ctx.whnf(type);
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while (is_pi(new_type)) {
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type = new_type;
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expr local;
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if (binfo)
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local = mk_local(mk_fresh_name(), binding_name(type), binding_domain(type), *binfo);
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else
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local = mk_local(mk_fresh_name(), binding_name(type), binding_domain(type), binding_info(type));
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telescope.push_back(local);
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type = instantiate(binding_body(type), local);
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new_type = ctx.whnf(type);
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}
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return type;
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}
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/* ----------------------------------------------
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Helper functions for creating basic operations
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---------------------------------------------- */
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static expr * g_true = nullptr;
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static expr * g_true_intro = nullptr;
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static expr * g_and = nullptr;
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static expr * g_and_intro = nullptr;
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static expr * g_and_elim_left = nullptr;
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static expr * g_and_elim_right = nullptr;
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expr mk_true() {
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return *g_true;
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}
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bool is_true(expr const & e) {
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return e == *g_true;
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}
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expr mk_true_intro() {
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return *g_true_intro;
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}
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bool is_and(expr const & e) {
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return is_app_of(e, get_and_name(), 2);
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}
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bool is_and(expr const & e, expr & arg1, expr & arg2) {
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if (is_and(e)) {
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arg1 = app_arg(app_fn(e));
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arg2 = app_arg(e);
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return true;
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} else {
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return false;
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}
|
|
}
|
|
|
|
expr mk_and(expr const & a, expr const & b) {
|
|
return mk_app(*g_and, a, b);
|
|
}
|
|
|
|
expr mk_and_intro(abstract_type_context & ctx, expr const & Ha, expr const & Hb) {
|
|
return mk_app(*g_and_intro, ctx.infer(Ha), ctx.infer(Hb), Ha, Hb);
|
|
}
|
|
|
|
expr mk_and_elim_left(abstract_type_context & ctx, expr const & H) {
|
|
expr a_and_b = ctx.whnf(ctx.infer(H));
|
|
return mk_app(*g_and_elim_left, app_arg(app_fn(a_and_b)), app_arg(a_and_b), H);
|
|
}
|
|
|
|
expr mk_and_elim_right(abstract_type_context & ctx, expr const & H) {
|
|
expr a_and_b = ctx.whnf(ctx.infer(H));
|
|
return mk_app(*g_and_elim_right, app_arg(app_fn(a_and_b)), app_arg(a_and_b), H);
|
|
}
|
|
|
|
expr mk_unit(level const & l) {
|
|
return mk_constant(get_punit_name(), {l});
|
|
}
|
|
|
|
expr mk_unit_mk(level const & l) {
|
|
return mk_constant(get_punit_star_name(), {l});
|
|
}
|
|
|
|
expr mk_pprod(abstract_type_context & ctx, expr const & A, expr const & B) {
|
|
level l1 = get_level(ctx, A);
|
|
level l2 = get_level(ctx, B);
|
|
return mk_app(mk_constant(get_pprod_name(), {l1, l2}), A, B);
|
|
}
|
|
|
|
expr mk_pprod_mk(abstract_type_context & ctx, expr const & a, expr const & b) {
|
|
expr A = ctx.infer(a);
|
|
expr B = ctx.infer(b);
|
|
level l1 = get_level(ctx, A);
|
|
level l2 = get_level(ctx, B);
|
|
return mk_app(mk_constant(get_pprod_mk_name(), {l1, l2}), A, B, a, b);
|
|
}
|
|
|
|
expr mk_pprod_fst(abstract_type_context & ctx, expr const & p) {
|
|
expr AxB = ctx.whnf(ctx.infer(p));
|
|
expr const & A = app_arg(app_fn(AxB));
|
|
expr const & B = app_arg(AxB);
|
|
return mk_app(mk_constant(get_pprod_fst_name(), const_levels(get_app_fn(AxB))), A, B, p);
|
|
}
|
|
|
|
expr mk_pprod_snd(abstract_type_context & ctx, expr const & p) {
|
|
expr AxB = ctx.whnf(ctx.infer(p));
|
|
expr const & A = app_arg(app_fn(AxB));
|
|
expr const & B = app_arg(AxB);
|
|
return mk_app(mk_constant(get_pprod_snd_name(), const_levels(get_app_fn(AxB))), A, B, p);
|
|
}
|
|
|
|
static expr * g_nat = nullptr;
|
|
static expr * g_nat_zero = nullptr;
|
|
static expr * g_nat_one = nullptr;
|
|
static expr * g_nat_bit0_fn = nullptr;
|
|
static expr * g_nat_bit1_fn = nullptr;
|
|
static expr * g_nat_add_fn = nullptr;
|
|
|
|
static void initialize_nat() {
|
|
g_nat = new expr(mk_constant(get_nat_name()));
|
|
g_nat_zero = new expr(mk_app(mk_constant(get_has_zero_zero_name(), {mk_level_zero()}), {*g_nat, mk_constant(get_nat_has_zero_name())}));
|
|
g_nat_one = new expr(mk_app(mk_constant(get_has_one_one_name(), {mk_level_zero()}), {*g_nat, mk_constant(get_nat_has_one_name())}));
|
|
g_nat_bit0_fn = new expr(mk_app(mk_constant(get_bit0_name(), {mk_level_zero()}), {*g_nat, mk_constant(get_nat_has_add_name())}));
|
|
g_nat_bit1_fn = new expr(mk_app(mk_constant(get_bit1_name(), {mk_level_zero()}), {*g_nat, mk_constant(get_nat_has_one_name()), mk_constant(get_nat_has_add_name())}));
|
|
g_nat_add_fn = new expr(mk_app(mk_constant(get_has_add_add_name(), {mk_level_zero()}), {*g_nat, mk_constant(get_nat_has_add_name())}));
|
|
}
|
|
|
|
static void finalize_nat() {
|
|
delete g_nat;
|
|
delete g_nat_zero;
|
|
delete g_nat_one;
|
|
delete g_nat_bit0_fn;
|
|
delete g_nat_bit1_fn;
|
|
delete g_nat_add_fn;
|
|
}
|
|
|
|
expr mk_nat_type() { return *g_nat; }
|
|
bool is_nat_type(expr const & e) { return e == *g_nat; }
|
|
expr mk_nat_zero() { return *g_nat_zero; }
|
|
expr mk_nat_one() { return *g_nat_one; }
|
|
expr mk_nat_bit0(expr const & e) { return mk_app(*g_nat_bit0_fn, e); }
|
|
expr mk_nat_bit1(expr const & e) { return mk_app(*g_nat_bit1_fn, e); }
|
|
expr mk_nat_add(expr const & e1, expr const & e2) { return mk_app(*g_nat_add_fn, e1, e2); }
|
|
|
|
static expr * g_int = nullptr;
|
|
|
|
static void initialize_int() {
|
|
g_int = new expr(mk_constant(get_int_name()));
|
|
}
|
|
|
|
static void finalize_int() {
|
|
delete g_int;
|
|
}
|
|
|
|
expr mk_int_type() { return *g_int; }
|
|
bool is_int_type(expr const & e) { return e == *g_int; }
|
|
|
|
static expr * g_char = nullptr;
|
|
|
|
expr mk_char_type() { return *g_char; }
|
|
|
|
static void initialize_char() {
|
|
g_char = new expr(mk_constant(get_char_name()));
|
|
}
|
|
|
|
static void finalize_char() {
|
|
delete g_char;
|
|
}
|
|
|
|
expr mk_unit(level const & l, bool prop) { return prop ? mk_true() : mk_unit(l); }
|
|
expr mk_unit_mk(level const & l, bool prop) { return prop ? mk_true_intro() : mk_unit_mk(l); }
|
|
|
|
expr mk_pprod(abstract_type_context & ctx, expr const & a, expr const & b, bool prop) {
|
|
return prop ? mk_and(a, b) : mk_pprod(ctx, a, b);
|
|
}
|
|
expr mk_pprod_mk(abstract_type_context & ctx, expr const & a, expr const & b, bool prop) {
|
|
return prop ? mk_and_intro(ctx, a, b) : mk_pprod_mk(ctx, a, b);
|
|
}
|
|
expr mk_pprod_fst(abstract_type_context & ctx, expr const & p, bool prop) {
|
|
return prop ? mk_and_elim_left(ctx, p) : mk_pprod_fst(ctx, p);
|
|
}
|
|
expr mk_pprod_snd(abstract_type_context & ctx, expr const & p, bool prop) {
|
|
return prop ? mk_and_elim_right(ctx, p) : mk_pprod_snd(ctx, p);
|
|
}
|
|
|
|
bool is_ite(expr const & e) {
|
|
return is_app_of(e, get_ite_name(), 5);
|
|
}
|
|
|
|
bool is_ite(expr const & e, expr & c, expr & H, expr & A, expr & t, expr & f) {
|
|
if (is_ite(e)) {
|
|
buffer<expr> args;
|
|
get_app_args(e, args);
|
|
lean_assert(args.size() == 5);
|
|
c = args[0]; H = args[1]; A = args[2]; t = args[3]; f = args[4];
|
|
return true;
|
|
} else {
|
|
return false;
|
|
}
|
|
}
|
|
|
|
bool is_iff(expr const & e) {
|
|
return is_app_of(e, get_iff_name(), 2);
|
|
}
|
|
|
|
bool is_iff(expr const & e, expr & lhs, expr & rhs) {
|
|
if (!is_iff(e))
|
|
return false;
|
|
lhs = app_arg(app_fn(e));
|
|
rhs = app_arg(e);
|
|
return true;
|
|
}
|
|
expr mk_iff(expr const & lhs, expr const & rhs) {
|
|
return mk_app(mk_constant(get_iff_name()), lhs, rhs);
|
|
}
|
|
expr mk_iff_refl(expr const & a) {
|
|
return mk_app(mk_constant(get_iff_refl_name()), a);
|
|
}
|
|
expr mk_propext(expr const & lhs, expr const & rhs, expr const & iff_pr) {
|
|
return mk_app(mk_constant(get_propext_name()), lhs, rhs, iff_pr);
|
|
}
|
|
|
|
expr mk_eq(abstract_type_context & ctx, expr const & lhs, expr const & rhs) {
|
|
expr A = ctx.whnf(ctx.infer(lhs));
|
|
level lvl = get_level(ctx, A);
|
|
return mk_app(mk_constant(get_eq_name(), {lvl}), A, lhs, rhs);
|
|
}
|
|
|
|
expr mk_eq_refl(abstract_type_context & ctx, expr const & a) {
|
|
expr A = ctx.whnf(ctx.infer(a));
|
|
level lvl = get_level(ctx, A);
|
|
return mk_app(mk_constant(get_eq_refl_name(), {lvl}), A, a);
|
|
}
|
|
|
|
expr mk_eq_symm(abstract_type_context & ctx, expr const & H) {
|
|
if (is_app_of(H, get_eq_refl_name()))
|
|
return H;
|
|
expr p = ctx.whnf(ctx.infer(H));
|
|
lean_assert(is_eq(p));
|
|
expr lhs = app_arg(app_fn(p));
|
|
expr rhs = app_arg(p);
|
|
expr A = ctx.infer(lhs);
|
|
level lvl = get_level(ctx, A);
|
|
return mk_app(mk_constant(get_eq_symm_name(), {lvl}), A, lhs, rhs, H);
|
|
}
|
|
|
|
expr mk_eq_trans(abstract_type_context & ctx, expr const & H1, expr const & H2) {
|
|
if (is_app_of(H1, get_eq_refl_name()))
|
|
return H2;
|
|
if (is_app_of(H2, get_eq_refl_name()))
|
|
return H1;
|
|
expr p1 = ctx.whnf(ctx.infer(H1));
|
|
expr p2 = ctx.whnf(ctx.infer(H2));
|
|
lean_assert(is_eq(p1) && is_eq(p2));
|
|
expr lhs1 = app_arg(app_fn(p1));
|
|
expr rhs1 = app_arg(p1);
|
|
expr rhs2 = app_arg(p2);
|
|
expr A = ctx.infer(lhs1);
|
|
level lvl = get_level(ctx, A);
|
|
return mk_app({mk_constant(get_eq_trans_name(), {lvl}), A, lhs1, rhs1, rhs2, H1, H2});
|
|
}
|
|
|
|
expr mk_eq_subst(abstract_type_context & ctx, expr const & motive,
|
|
expr const & x, expr const & y, expr const & xeqy, expr const & h) {
|
|
expr A = ctx.infer(x);
|
|
level l1 = get_level(ctx, A);
|
|
expr r = mk_constant(get_eq_subst_name(), {l1});
|
|
return mk_app({r, A, x, y, motive, xeqy, h});
|
|
}
|
|
|
|
expr mk_eq_subst(abstract_type_context & ctx, expr const & motive, expr const & xeqy, expr const & h) {
|
|
expr xeqy_type = ctx.whnf(ctx.infer(xeqy));
|
|
return mk_eq_subst(ctx, motive, app_arg(app_fn(xeqy_type)), app_arg(xeqy_type), xeqy, h);
|
|
}
|
|
|
|
expr mk_congr_arg(abstract_type_context & ctx, expr const & f, expr const & H) {
|
|
expr eq = ctx.relaxed_whnf(ctx.infer(H));
|
|
expr pi = ctx.relaxed_whnf(ctx.infer(f));
|
|
expr A, B, lhs, rhs;
|
|
lean_verify(is_eq(eq, A, lhs, rhs));
|
|
lean_assert(is_arrow(pi));
|
|
B = binding_body(pi);
|
|
level lvl_1 = get_level(ctx, A);
|
|
level lvl_2 = get_level(ctx, B);
|
|
return ::lean::mk_app({mk_constant(get_congr_arg_name(), {lvl_1, lvl_2}), A, B, lhs, rhs, f, H});
|
|
}
|
|
|
|
expr mk_subsingleton_elim(abstract_type_context & ctx, expr const & h, expr const & x, expr const & y) {
|
|
expr A = ctx.infer(x);
|
|
level l = get_level(ctx, A);
|
|
expr r = mk_constant(get_subsingleton_elim_name(), {l});
|
|
return mk_app({r, A, h, x, y});
|
|
}
|
|
|
|
expr mk_heq(abstract_type_context & ctx, expr const & lhs, expr const & rhs) {
|
|
expr A = ctx.whnf(ctx.infer(lhs));
|
|
expr B = ctx.whnf(ctx.infer(rhs));
|
|
level lvl = get_level(ctx, A);
|
|
return mk_app(mk_constant(get_heq_name(), {lvl}), A, lhs, B, rhs);
|
|
}
|
|
|
|
bool is_eq_rec_core(expr const & e) {
|
|
expr const & fn = get_app_fn(e);
|
|
return is_constant(fn) && const_name(fn) == get_eq_rec_name();
|
|
}
|
|
|
|
bool is_eq_rec(expr const & e) {
|
|
expr const & fn = get_app_fn(e);
|
|
if (!is_constant(fn))
|
|
return false;
|
|
return const_name(fn) == get_eq_rec_name();
|
|
}
|
|
|
|
bool is_eq_drec(expr const & e) {
|
|
expr const & fn = get_app_fn(e);
|
|
if (!is_constant(fn))
|
|
return false;
|
|
return const_name(fn) == get_eq_drec_name();
|
|
}
|
|
|
|
bool is_eq(expr const & e) {
|
|
return is_app_of(e, get_eq_name(), 3);
|
|
}
|
|
|
|
bool is_eq(expr const & e, expr & lhs, expr & rhs) {
|
|
if (!is_eq(e))
|
|
return false;
|
|
lhs = app_arg(app_fn(e));
|
|
rhs = app_arg(e);
|
|
return true;
|
|
}
|
|
|
|
bool is_eq(expr const & e, expr & A, expr & lhs, expr & rhs) {
|
|
if (!is_eq(e))
|
|
return false;
|
|
A = app_arg(app_fn(app_fn(e)));
|
|
lhs = app_arg(app_fn(e));
|
|
rhs = app_arg(e);
|
|
return true;
|
|
}
|
|
|
|
bool is_eq_a_a(expr const & e) {
|
|
if (!is_eq(e))
|
|
return false;
|
|
expr lhs = app_arg(app_fn(e));
|
|
expr rhs = app_arg(e);
|
|
return lhs == rhs;
|
|
}
|
|
|
|
bool is_eq_a_a(abstract_type_context & ctx, expr const & e) {
|
|
if (!is_eq(e))
|
|
return false;
|
|
expr lhs = app_arg(app_fn(e));
|
|
expr rhs = app_arg(e);
|
|
return ctx.is_def_eq(lhs, rhs);
|
|
}
|
|
|
|
bool is_heq(expr const & e) {
|
|
return is_app_of(e, get_heq_name(), 4);
|
|
}
|
|
|
|
bool is_heq(expr const & e, expr & A, expr & lhs, expr & B, expr & rhs) {
|
|
if (is_heq(e)) {
|
|
buffer<expr> args;
|
|
get_app_args(e, args);
|
|
lean_assert(args.size() == 4);
|
|
A = args[0]; lhs = args[1]; B = args[2]; rhs = args[3];
|
|
return true;
|
|
} else {
|
|
return false;
|
|
}
|
|
}
|
|
|
|
bool is_heq(expr const & e, expr & lhs, expr & rhs) {
|
|
expr A, B;
|
|
return is_heq(e, A, lhs, B, rhs);
|
|
}
|
|
|
|
expr mk_cast(abstract_type_context & ctx, expr const & H, expr const & e) {
|
|
expr type = ctx.relaxed_whnf(ctx.infer(H));
|
|
expr A, B;
|
|
if (!is_eq(type, A, B))
|
|
throw exception("cast failed, equality proof expected");
|
|
level lvl = get_level(ctx, A);
|
|
return mk_app(mk_constant(get_cast_name(), {lvl}), A, B, H, e);
|
|
}
|
|
|
|
expr mk_false() {
|
|
return mk_constant(get_false_name());
|
|
}
|
|
|
|
expr mk_empty() {
|
|
return mk_constant(get_empty_name());
|
|
}
|
|
|
|
bool is_false(expr const & e) {
|
|
return is_constant(e) && const_name(e) == get_false_name();
|
|
}
|
|
|
|
bool is_empty(expr const & e) {
|
|
return is_constant(e) && const_name(e) == get_empty_name();
|
|
}
|
|
|
|
expr mk_false_rec(abstract_type_context & ctx, expr const & f, expr const & t) {
|
|
level t_lvl = get_level(ctx, t);
|
|
return mk_app(mk_constant(get_false_rec_name(), {t_lvl}), t, f);
|
|
}
|
|
|
|
bool is_or(expr const & e) {
|
|
return is_app_of(e, get_or_name(), 2);
|
|
}
|
|
|
|
bool is_or(expr const & e, expr & A, expr & B) {
|
|
if (is_or(e)) {
|
|
A = app_arg(app_fn(e));
|
|
B = app_arg(e);
|
|
return true;
|
|
} else {
|
|
return false;
|
|
}
|
|
}
|
|
|
|
bool is_not(expr const & e, expr & a) {
|
|
if (is_app_of(e, get_not_name(), 1)) {
|
|
a = app_arg(e);
|
|
return true;
|
|
} else if (is_pi(e) && is_false(binding_body(e))) {
|
|
a = binding_domain(e);
|
|
return true;
|
|
} else {
|
|
return false;
|
|
}
|
|
}
|
|
|
|
bool is_not_or_ne(expr const & e, expr & a) {
|
|
if (is_not(e, a)) {
|
|
return true;
|
|
} else if (is_app_of(e, get_ne_name(), 3)) {
|
|
buffer<expr> args;
|
|
expr const & fn = get_app_args(e, args);
|
|
expr new_fn = mk_constant(get_eq_name(), const_levels(fn));
|
|
a = mk_app(new_fn, args);
|
|
return true;
|
|
} else {
|
|
return false;
|
|
}
|
|
}
|
|
|
|
expr mk_not(expr const & e) {
|
|
return mk_app(mk_constant(get_not_name()), e);
|
|
}
|
|
|
|
expr mk_absurd(abstract_type_context & ctx, expr const & t, expr const & e, expr const & not_e) {
|
|
level t_lvl = get_level(ctx, t);
|
|
expr e_type = ctx.infer(e);
|
|
return mk_app(mk_constant(get_absurd_name(), {t_lvl}), e_type, t, e, not_e);
|
|
}
|
|
|
|
bool is_exists(expr const & e, expr & A, expr & p) {
|
|
if (is_app_of(e, get_Exists_name(), 2)) {
|
|
A = app_arg(app_fn(e));
|
|
p = app_arg(e);
|
|
return true;
|
|
} else {
|
|
return false;
|
|
}
|
|
}
|
|
|
|
bool is_exists(expr const & e) {
|
|
return is_app_of(e, get_Exists_name(), 2);
|
|
}
|
|
|
|
optional<expr> get_binary_op(expr const & e) {
|
|
if (!is_app(e) || !is_app(app_fn(e)))
|
|
return none_expr();
|
|
return some_expr(app_fn(app_fn(e)));
|
|
}
|
|
|
|
optional<expr> get_binary_op(expr const & e, expr & arg1, expr & arg2) {
|
|
if (auto op = get_binary_op(e)) {
|
|
arg1 = app_arg(app_fn(e));
|
|
arg2 = app_arg(e);
|
|
return some_expr(*op);
|
|
} else {
|
|
return none_expr();
|
|
}
|
|
}
|
|
|
|
expr mk_nary_app(expr const & op, buffer<expr> const & nary_args) {
|
|
return mk_nary_app(op, nary_args.size(), nary_args.data());
|
|
}
|
|
|
|
expr mk_nary_app(expr const & op, unsigned num_nary_args, expr const * nary_args) {
|
|
lean_assert(num_nary_args >= 2);
|
|
// f x1 x2 x3 ==> f x1 (f x2 x3)
|
|
expr e = mk_app(op, nary_args[num_nary_args - 2], nary_args[num_nary_args - 1]);
|
|
for (int i = num_nary_args - 3; i >= 0; --i) {
|
|
e = mk_app(op, nary_args[i], e);
|
|
}
|
|
return e;
|
|
}
|
|
|
|
bool is_annotated_lamba(expr const & e) {
|
|
return
|
|
is_lambda(e) ||
|
|
(is_annotation(e) && is_lambda(get_nested_annotation_arg(e)));
|
|
}
|
|
|
|
bool is_annotated_head_beta(expr const & t) {
|
|
return is_app(t) && is_annotated_lamba(get_app_fn(t));
|
|
}
|
|
|
|
expr annotated_head_beta_reduce(expr const & t) {
|
|
if (!is_annotated_head_beta(t)) {
|
|
return t;
|
|
} else {
|
|
buffer<expr> args;
|
|
expr f = get_app_rev_args(t, args);
|
|
if (is_annotation(f))
|
|
f = get_nested_annotation_arg(f);
|
|
lean_assert(is_lambda(f));
|
|
return annotated_head_beta_reduce(apply_beta(f, args.size(), args.data()));
|
|
}
|
|
}
|
|
|
|
expr try_eta(expr const & e) {
|
|
if (is_lambda(e)) {
|
|
expr const & b = binding_body(e);
|
|
if (is_lambda(b)) {
|
|
expr new_b = try_eta(b);
|
|
if (is_eqp(b, new_b)) {
|
|
return e;
|
|
} else if (is_app(new_b) && is_var(app_arg(new_b), 0) && !has_free_var(app_fn(new_b), 0)) {
|
|
return lower_free_vars(app_fn(new_b), 1);
|
|
} else {
|
|
return update_binding(e, binding_domain(e), new_b);
|
|
}
|
|
} else if (is_app(b) && is_var(app_arg(b), 0) && !has_free_var(app_fn(b), 0)) {
|
|
return lower_free_vars(app_fn(b), 1);
|
|
} else {
|
|
return e;
|
|
}
|
|
} else {
|
|
return e;
|
|
}
|
|
}
|
|
|
|
template<bool Eta, bool Beta>
|
|
class eta_beta_reduce_fn : public replace_visitor {
|
|
public:
|
|
virtual expr visit_app(expr const & e) override {
|
|
expr e1 = replace_visitor::visit_app(e);
|
|
if (Beta && is_head_beta(e1)) {
|
|
return visit(head_beta_reduce(e1));
|
|
} else {
|
|
return e1;
|
|
}
|
|
}
|
|
|
|
virtual expr visit_lambda(expr const & e) override {
|
|
expr e1 = replace_visitor::visit_lambda(e);
|
|
if (Eta) {
|
|
while (true) {
|
|
expr e2 = try_eta(e1);
|
|
if (is_eqp(e1, e2))
|
|
return e1;
|
|
else
|
|
e1 = e2;
|
|
}
|
|
} else {
|
|
return e1;
|
|
}
|
|
}
|
|
};
|
|
|
|
expr beta_reduce(expr t) {
|
|
return eta_beta_reduce_fn<false, true>()(t);
|
|
}
|
|
|
|
expr eta_reduce(expr t) {
|
|
return eta_beta_reduce_fn<true, false>()(t);
|
|
}
|
|
|
|
expr beta_eta_reduce(expr t) {
|
|
return eta_beta_reduce_fn<true, true>()(t);
|
|
}
|
|
|
|
expr infer_implicit_params(expr const & type, unsigned nparams, implicit_infer_kind k) {
|
|
switch (k) {
|
|
case implicit_infer_kind::Implicit: {
|
|
bool strict = true;
|
|
return infer_implicit(type, nparams, strict);
|
|
}
|
|
case implicit_infer_kind::RelaxedImplicit: {
|
|
bool strict = false;
|
|
return infer_implicit(type, nparams, strict);
|
|
}
|
|
case implicit_infer_kind::None:
|
|
return type;
|
|
}
|
|
lean_unreachable(); // LCOV_EXCL_LINE
|
|
}
|
|
|
|
bool get_constructor_rec_args(environment const & env, expr const & e, buffer<pair<expr, unsigned>> & rec_args) {
|
|
type_checker ctx(env);
|
|
buffer<expr> args;
|
|
expr const & fn = get_app_args(e, args);
|
|
if (!is_constant(fn)) return false;
|
|
optional<name> I_name = inductive::is_intro_rule(env, const_name(fn));
|
|
if (!I_name) return false;
|
|
expr type = env.get(const_name(fn)).get_type();
|
|
buffer<expr> tele;
|
|
to_telescope(ctx, type, tele);
|
|
if (tele.size() != args.size()) return false;
|
|
for (unsigned i = 0; i < tele.size(); i++) {
|
|
expr d = tele[i];
|
|
buffer<expr> tele_tele;
|
|
expr r = to_telescope(ctx, mlocal_type(d), tele_tele);
|
|
expr fn = get_app_fn(r);
|
|
if (is_constant(fn, *I_name)) {
|
|
rec_args.push_back(mk_pair(args[i], tele_tele.size()));
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
static expr * g_bool = nullptr;
|
|
static expr * g_bool_tt = nullptr;
|
|
static expr * g_bool_ff = nullptr;
|
|
|
|
void initialize_bool() {
|
|
g_bool = new expr(mk_constant(get_bool_name()));
|
|
g_bool_ff = new expr(mk_constant(get_bool_ff_name()));
|
|
g_bool_tt = new expr(mk_constant(get_bool_tt_name()));
|
|
}
|
|
|
|
void finalize_bool() {
|
|
delete g_bool;
|
|
delete g_bool_ff;
|
|
delete g_bool_tt;
|
|
}
|
|
|
|
expr mk_bool() { return *g_bool; }
|
|
expr mk_bool_tt() { return *g_bool_tt; }
|
|
expr mk_bool_ff() { return *g_bool_ff; }
|
|
expr to_bool_expr(bool b) { return b ? mk_bool_tt() : mk_bool_ff(); }
|
|
|
|
name get_dep_recursor(environment const & env, name const & n) {
|
|
if (is_inductive_predicate(env, n))
|
|
return name(n, "drec");
|
|
else
|
|
return name(n, "rec");
|
|
}
|
|
|
|
name get_dep_cases_on(environment const & env, name const & n) {
|
|
if (is_inductive_predicate(env, n))
|
|
return name(n, "dcases_on");
|
|
else
|
|
return name(n, "cases_on");
|
|
}
|
|
|
|
static char const * g_aux_meta_rec_prefix = "_meta_aux";
|
|
|
|
name mk_aux_meta_rec_name(name const & n) {
|
|
return name(n, g_aux_meta_rec_prefix);
|
|
}
|
|
|
|
optional<name> is_aux_meta_rec_name(name const & n) {
|
|
if (!n.is_atomic() && n.is_string() && strcmp(n.get_string(), g_aux_meta_rec_prefix) == 0) {
|
|
return optional<name>(n.get_prefix());
|
|
} else {
|
|
return optional<name>();
|
|
}
|
|
}
|
|
|
|
void initialize_library_util() {
|
|
g_true = new expr(mk_constant(get_true_name()));
|
|
g_true_intro = new expr(mk_constant(get_true_intro_name()));
|
|
g_and = new expr(mk_constant(get_and_name()));
|
|
g_and_intro = new expr(mk_constant(get_and_intro_name()));
|
|
g_and_elim_left = new expr(mk_constant(get_and_elim_left_name()));
|
|
g_and_elim_right = new expr(mk_constant(get_and_elim_right_name()));
|
|
initialize_nat();
|
|
initialize_int();
|
|
initialize_char();
|
|
initialize_bool();
|
|
}
|
|
|
|
void finalize_library_util() {
|
|
finalize_bool();
|
|
finalize_int();
|
|
finalize_nat();
|
|
finalize_char();
|
|
delete g_true;
|
|
delete g_true_intro;
|
|
delete g_and;
|
|
delete g_and_intro;
|
|
delete g_and_elim_left;
|
|
delete g_and_elim_right;
|
|
}
|
|
}
|