예제 #1
0
파일: find_cmd.cpp 프로젝트: cpehle/lean
bool match_pattern(type_checker & tc, expr const & pattern, declaration const & d, unsigned max_steps, bool cheap) {
    name_generator ngen = tc.mk_ngen();
     buffer<level> ls;
    unsigned num_ls = d.get_num_univ_params();
    for (unsigned i = 0; i < num_ls; i++)
        ls.push_back(mk_meta_univ(ngen.next()));
    expr dt        = instantiate_type_univ_params(d, to_list(ls.begin(), ls.end()));

    unsigned num_e = get_expect_num_args(tc, pattern);
    unsigned num_d = get_expect_num_args(tc, dt);
    if (num_e > num_d)
        return false;
    for (unsigned i = 0; i < num_d - num_e; i++) {
        dt         = tc.whnf(dt).first;
        expr local = mk_local(ngen.next(), binding_domain(dt));
        dt         = instantiate(binding_body(dt), local);
    }
    try {
        unifier_config cfg;
        cfg.m_max_steps            = max_steps;
        cfg.m_kind                 = cheap ? unifier_kind::Cheap : unifier_kind::Liberal;
        cfg.m_ignore_context_check = true;
        auto r = unify(tc.env(), pattern, dt, tc.mk_ngen(), substitution(), cfg);
        return static_cast<bool>(r.pull());
    } catch (exception&) {
        return false;
    }
}
예제 #2
0
static proof_state_seq apply_tactic_core(environment const & env, io_state const & ios, proof_state const & s,
                                         expr const & _e, buffer<constraint> & cs,
                                         add_meta_kind add_meta, subgoals_action_kind subgoals_action,
                                         optional<unifier_kind> const & uk = optional<unifier_kind>()) {
    goals const & gs = s.get_goals();
    if (empty(gs)) {
        throw_no_goal_if_enabled(s);
        return proof_state_seq();
    }
    bool class_inst   = get_apply_class_instance(ios.get_options());
    name_generator ngen = s.get_ngen();
    std::shared_ptr<type_checker> tc(mk_type_checker(env, ngen.mk_child()));
    goal  g           = head(gs);
    goals tail_gs     = tail(gs);
    expr  t           = g.get_type();
    expr  e           = _e;
    auto e_t_cs       = tc->infer(e);
    e_t_cs.second.linearize(cs);
    expr  e_t         = e_t_cs.first;
    buffer<expr> metas;
    local_context ctx;
    bool initialized_ctx = false;
    unifier_config cfg(ios.get_options());
    if (uk)
        cfg.m_kind = *uk;
    if (add_meta != DoNotAdd) {
        unsigned num_e_t = get_expect_num_args(*tc, e_t);
        if (add_meta == AddDiff) {
            unsigned num_t   = get_expect_num_args(*tc, t);
            if (num_t <= num_e_t)
                num_e_t -= num_t;
            else
                num_e_t = 0;
        } else {
            lean_assert(add_meta == AddAll);
        }
        for (unsigned i = 0; i < num_e_t; i++) {
            auto e_t_cs = tc->whnf(e_t);
            e_t_cs.second.linearize(cs);
            e_t        = e_t_cs.first;
            expr meta;
            if (class_inst && binding_info(e_t).is_inst_implicit()) {
                if (!initialized_ctx) {
                    ctx = g.to_local_context();
                    initialized_ctx = true;
                }
                bool use_local_insts = true;
                bool is_strict       = false;
                auto mc = mk_class_instance_elaborator(
                    env, ios, ctx, ngen.next(), optional<name>(),
                    use_local_insts, is_strict,
                    some_expr(head_beta_reduce(binding_domain(e_t))), e.get_tag(), cfg, nullptr);
                meta    = mc.first;
                cs.push_back(mc.second);
            } else {
                meta  = g.mk_meta(ngen.next(), head_beta_reduce(binding_domain(e_t)));
            }
            e          = mk_app(e, meta);
            e_t        = instantiate(binding_body(e_t), meta);
            metas.push_back(meta);
        }
    }
    metavar_closure cls(t);
    cls.mk_constraints(s.get_subst(), justification());
    pair<bool, constraint_seq> dcs = tc->is_def_eq(t, e_t);
    if (!dcs.first) {
        throw_tactic_exception_if_enabled(s, [=](formatter const & fmt) {
                format r = format("invalid 'apply' tactic, failed to unify");
                r       += pp_indent_expr(fmt, t);
                r       += compose(line(), format("with"));
                r       += pp_indent_expr(fmt, e_t);
                return r;
            });
        return proof_state_seq();
    }
    dcs.second.linearize(cs);
    unify_result_seq rseq = unify(env, cs.size(), cs.data(), ngen.mk_child(), s.get_subst(), cfg);
    list<expr> meta_lst   = to_list(metas.begin(), metas.end());
    return map2<proof_state>(rseq, [=](pair<substitution, constraints> const & p) -> proof_state {
            substitution const & subst    = p.first;
            constraints const & postponed = p.second;
            name_generator new_ngen(ngen);
            substitution new_subst = subst;
            expr new_e = new_subst.instantiate_all(e);
            assign(new_subst, g, new_e);
            goals new_gs = tail_gs;
            if (subgoals_action != IgnoreSubgoals) {
                buffer<expr> metas;
                for (auto m : meta_lst) {
                    if (!new_subst.is_assigned(get_app_fn(m)))
                        metas.push_back(m);
                }
                if (subgoals_action == AddRevSubgoals) {
                    for (unsigned i = 0; i < metas.size(); i++)
                        new_gs = cons(goal(metas[i], new_subst.instantiate_all(tc->infer(metas[i]).first)), new_gs);
                } else {
                    lean_assert(subgoals_action == AddSubgoals || subgoals_action == AddAllSubgoals);
                    if (subgoals_action == AddSubgoals)
                        remove_redundant_metas(metas);
                    unsigned i = metas.size();
                    while (i > 0) {
                        --i;
                        new_gs = cons(goal(metas[i], new_subst.instantiate_all(tc->infer(metas[i]).first)), new_gs);
                    }
                }
            }
            return proof_state(s, new_gs, new_subst, new_ngen, postponed);
        });
}