bool apply(expr const & a, expr const & b) {
if (is_eqp(a, b)) return true;
if (a.hash() != b.hash()) return false;
if (a.kind() != b.kind()) return false;
if (is_var(a)) return var_idx(a) == var_idx(b);
if (m_cache.check(a, b))
return true;
switch (a.kind()) {
case expr_kind::Var:
lean_unreachable(); // LCOV_EXCL_LINE
case expr_kind::Constant:
return
const_name(a) == const_name(b) &&
compare(const_levels(a), const_levels(b), [](level const & l1, level const & l2) { return l1 == l2; });
case expr_kind::Meta:
return
mlocal_name(a) == mlocal_name(b) &&
apply(mlocal_type(a), mlocal_type(b));
case expr_kind::Local:
return
mlocal_name(a) == mlocal_name(b) &&
apply(mlocal_type(a), mlocal_type(b)) &&
(!CompareBinderInfo || local_pp_name(a) == local_pp_name(b)) &&
(!CompareBinderInfo || local_info(a) == local_info(b));
case expr_kind::App:
check_system();
return
apply(app_fn(a), app_fn(b)) &&
apply(app_arg(a), app_arg(b));
case expr_kind::Lambda: case expr_kind::Pi:
check_system();
return
apply(binding_domain(a), binding_domain(b)) &&
apply(binding_body(a), binding_body(b)) &&
(!CompareBinderInfo || binding_name(a) == binding_name(b)) &&
(!CompareBinderInfo || binding_info(a) == binding_info(b));
case expr_kind::Let:
check_system();
return
apply(let_type(a), let_type(b)) &&
apply(let_value(a), let_value(b)) &&
apply(let_body(a), let_body(b)) &&
(!CompareBinderInfo || let_name(a) == let_name(b));
case expr_kind::Sort:
return sort_level(a) == sort_level(b);
case expr_kind::Macro:
check_system();
if (macro_def(a) != macro_def(b) || macro_num_args(a) != macro_num_args(b))
return false;
for (unsigned i = 0; i < macro_num_args(a); i++) {
if (!apply(macro_arg(a, i), macro_arg(b, i)))
return false;
}
return true;
}
lean_unreachable(); // LCOV_EXCL_LINE
}
bool is_lt(expr const & a, expr const & b, bool use_hash) {
if (is_eqp(a, b)) return false;
unsigned wa = get_weight(a);
unsigned wb = get_weight(b);
if (wa < wb) return true;
if (wa > wb) return false;
if (a.kind() != b.kind()) return a.kind() < b.kind();
if (use_hash) {
if (a.hash() < b.hash()) return true;
if (a.hash() > b.hash()) return false;
}
if (a == b) return false;
switch (a.kind()) {
case expr_kind::Var:
return var_idx(a) < var_idx(b);
case expr_kind::Constant:
if (const_name(a) != const_name(b))
return const_name(a) < const_name(b);
else
return is_lt(const_levels(a), const_levels(b), use_hash);
case expr_kind::App:
if (app_fn(a) != app_fn(b))
return is_lt(app_fn(a), app_fn(b), use_hash);
else
return is_lt(app_arg(a), app_arg(b), use_hash);
case expr_kind::Lambda: case expr_kind::Pi:
if (binding_domain(a) != binding_domain(b))
return is_lt(binding_domain(a), binding_domain(b), use_hash);
else
return is_lt(binding_body(a), binding_body(b), use_hash);
case expr_kind::Let:
if (let_type(a) != let_type(b))
return is_lt(let_type(a), let_type(b), use_hash);
else if (let_value(a) != let_value(b))
return is_lt(let_value(a), let_value(b), use_hash);
else
return is_lt(let_body(a), let_body(b), use_hash);
case expr_kind::Sort:
return is_lt(sort_level(a), sort_level(b), use_hash);
case expr_kind::Local: case expr_kind::Meta:
if (mlocal_name(a) != mlocal_name(b))
return mlocal_name(a) < mlocal_name(b);
else
return is_lt(mlocal_type(a), mlocal_type(b), use_hash);
case expr_kind::Macro:
if (macro_def(a) != macro_def(b))
return macro_def(a) < macro_def(b);
if (macro_num_args(a) != macro_num_args(b))
return macro_num_args(a) < macro_num_args(b);
for (unsigned i = 0; i < macro_num_args(a); i++) {
if (macro_arg(a, i) != macro_arg(b, i))
return is_lt(macro_arg(a, i), macro_arg(b, i), use_hash);
}
return false;
}
lean_unreachable(); // LCOV_EXCL_LINE
}
bool expr_eq_fn::apply(expr const & a, expr const & b) {
if (is_eqp(a, b)) return true;
if (a.hash() != b.hash()) return false;
if (a.kind() != b.kind()) return false;
if (is_var(a)) return var_idx(a) == var_idx(b);
if (m_counter >= LEAN_EQ_CACHE_THRESHOLD && is_shared(a) && is_shared(b)) {
auto p = std::make_pair(a.raw(), b.raw());
if (!m_eq_visited)
m_eq_visited.reset(new expr_cell_pair_set);
if (m_eq_visited->find(p) != m_eq_visited->end())
return true;
m_eq_visited->insert(p);
}
check_system("expression equality test");
switch (a.kind()) {
case expr_kind::Var:
lean_unreachable(); // LCOV_EXCL_LINE
case expr_kind::Constant:
return
const_name(a) == const_name(b) &&
compare(const_levels(a), const_levels(b), [](level const & l1, level const & l2) { return l1 == l2; });
case expr_kind::Local: case expr_kind::Meta:
return
mlocal_name(a) == mlocal_name(b) &&
apply(mlocal_type(a), mlocal_type(b));
case expr_kind::App:
m_counter++;
return
apply(app_fn(a), app_fn(b)) &&
apply(app_arg(a), app_arg(b));
case expr_kind::Lambda: case expr_kind::Pi:
m_counter++;
return
apply(binding_domain(a), binding_domain(b)) &&
apply(binding_body(a), binding_body(b)) &&
(!m_compare_binder_info || binding_info(a) == binding_info(b));
case expr_kind::Sort:
return sort_level(a) == sort_level(b);
case expr_kind::Macro:
m_counter++;
if (macro_def(a) != macro_def(b) || macro_num_args(a) != macro_num_args(b))
return false;
for (unsigned i = 0; i < macro_num_args(a); i++) {
if (!apply(macro_arg(a, i), macro_arg(b, i)))
return false;
}
return true;
case expr_kind::Let:
m_counter++;
return
apply(let_type(a), let_type(b)) &&
apply(let_value(a), let_value(b)) &&
apply(let_body(a), let_body(b));
}
lean_unreachable(); // LCOV_EXCL_LINE
}
bool is_lt_no_level_params(expr const & a, expr const & b) {
if (is_eqp(a, b)) return false;
unsigned wa = get_weight(a);
unsigned wb = get_weight(b);
if (wa < wb) return true;
if (wa > wb) return false;
if (a.kind() != b.kind()) return a.kind() < b.kind();
switch (a.kind()) {
case expr_kind::Var:
return var_idx(a) < var_idx(b);
case expr_kind::Constant:
if (const_name(a) != const_name(b))
return const_name(a) < const_name(b);
else
return is_lt_no_level_params(const_levels(a), const_levels(b));
case expr_kind::App:
if (is_lt_no_level_params(app_fn(a), app_fn(b)))
return true;
else if (is_lt_no_level_params(app_fn(b), app_fn(a)))
return false;
else
return is_lt_no_level_params(app_arg(a), app_arg(b));
case expr_kind::Lambda: case expr_kind::Pi:
if (is_lt_no_level_params(binding_domain(a), binding_domain(b)))
return true;
else if (is_lt_no_level_params(binding_domain(b), binding_domain(a)))
return false;
else
return is_lt_no_level_params(binding_body(a), binding_body(b));
case expr_kind::Sort:
return is_lt_no_level_params(sort_level(a), sort_level(b));
case expr_kind::Local: case expr_kind::Meta:
if (mlocal_name(a) != mlocal_name(b))
return mlocal_name(a) < mlocal_name(b);
else
return is_lt_no_level_params(mlocal_type(a), mlocal_type(b));
case expr_kind::Macro:
if (macro_def(a) != macro_def(b))
return macro_def(a) < macro_def(b);
if (macro_num_args(a) != macro_num_args(b))
return macro_num_args(a) < macro_num_args(b);
for (unsigned i = 0; i < macro_num_args(a); i++) {
if (is_lt_no_level_params(macro_arg(a, i), macro_arg(b, i)))
return true;
else if (is_lt_no_level_params(macro_arg(b, i), macro_arg(a, i)))
return false;
}
return false;
}
lean_unreachable();
}
void forward_branch_extension::index_expr(expr const & e) {
// TODO(dhs): index the target when it gets updated
if (auto head_idx = to_head_index(e)) {
m_index.insert(head_index(e), e);
}
switch (e.kind()) {
case expr_kind::Var:
lean_unreachable(); // LCOV_EXCL_LINE
case expr_kind::Local:
case expr_kind::Meta:
case expr_kind::Sort:
case expr_kind::Constant:
case expr_kind::Macro: // TODO(dhs): do I unfold macros?
break;
case expr_kind::Lambda:
case expr_kind::Pi:
// TODO(dhs): confirm that I only index quantified-free hypotheses
break;
case expr_kind::Let:
// Let-expressions must be unfolded before invoking this method
lean_unreachable();
case expr_kind::App:
index_expr(app_fn(e));
index_expr(app_arg(e));
break;
}
}
expr apply(expr const & a) {
check_system("max_sharing");
auto r = m_expr_cache.find(a);
if (r != m_expr_cache.end())
return *r;
expr res;
switch (a.kind()) {
case expr_kind::Var:
res = a;
break;
case expr_kind::Constant:
res = update_constant(a, map(const_levels(a), [&](level const & l) { return apply(l); }));
break;
case expr_kind::Sort:
res = update_sort(a, apply(sort_level(a)));
break;
case expr_kind::App:
res = update_app(a, apply(app_fn(a)), apply(app_arg(a)));
break;
case expr_kind::Lambda: case expr_kind::Pi:
res = update_binding(a, apply(binding_domain(a)), apply(binding_body(a)));
break;
case expr_kind::Meta: case expr_kind::Local:
res = update_mlocal(a, apply(mlocal_type(a)));
break;
case expr_kind::Macro: {
buffer<expr> new_args;
for (unsigned i = 0; i < macro_num_args(a); i++)
new_args.push_back(macro_arg(a, i));
res = update_macro(a, new_args.size(), new_args.data());
break;
}}
m_expr_cache.insert(res);
return res;
}
expr const & get_app_fn(expr const & e) {
expr const * it = &e;
while (is_app(*it)) {
it = &(app_fn(*it));
}
return *it;
}
expr const & get_app_rev_args(expr const & e, buffer<expr> & args) {
expr const * it = &e;
while (is_app(*it)) {
args.push_back(app_arg(*it));
it = &(app_fn(*it));
}
return *it;
}
// Return true iff lhs is of the form (B (x : ?m1), ?m2) or (B (x : ?m1), ?m2 x),
// where B is lambda or Pi
static bool is_valid_congr_rule_binding_lhs(expr const & lhs, name_set & found_mvars) {
lean_assert(is_binding(lhs));
expr const & d = binding_domain(lhs);
expr const & b = binding_body(lhs);
if (!is_metavar(d))
return false;
if (is_metavar(b) && b != d) {
found_mvars.insert(mlocal_name(b));
found_mvars.insert(mlocal_name(d));
return true;
}
if (is_app(b) && is_metavar(app_fn(b)) && is_var(app_arg(b), 0) && app_fn(b) != d) {
found_mvars.insert(mlocal_name(app_fn(b)));
found_mvars.insert(mlocal_name(d));
return true;
}
return false;
}
unsigned get_app_num_args(expr const & e) {
expr const * it = &e;
unsigned n = 0;
while (is_app(*it)) {
it = &(app_fn(*it));
n++;
}
return n;
}
expr const & get_app_args(expr const & e, buffer<expr> & args) {
unsigned sz = args.size();
expr const * it = &e;
while (is_app(*it)) {
args.push_back(app_arg(*it));
it = &(app_fn(*it));
}
std::reverse(args.begin() + sz, args.end());
return *it;
}
unsigned abstract_expr_manager::hash(expr const & e) {
unsigned h;
switch (e.kind()) {
case expr_kind::Constant:
case expr_kind::Local:
case expr_kind::Meta:
case expr_kind::Sort:
case expr_kind::Var:
case expr_kind::Macro:
return e.hash();
case expr_kind::Lambda:
case expr_kind::Pi:
h = hash(binding_domain(e));
// Remark binding_domain(e) may contain de-bruijn variables.
// We can instantiate them eagerly as we do here, or lazily.
// The lazy approach is potentially more efficient, but we would have
// to use something more sophisticated than an instantiate_rev at expr_kind::App
m_locals.push_back(instantiate_rev(m_tctx.mk_tmp_local(binding_domain(e)), m_locals.size(), m_locals.data()));
h = ::lean::hash(h, hash(binding_body(e)));
m_locals.pop_back();
return h;
case expr_kind::Let:
// Let-expressions must be unfolded before invoking this method
lean_unreachable();
case expr_kind::App:
buffer<expr> args;
expr const & f = get_app_args(e, args);
unsigned prefix_sz = m_congr_lemma_manager.get_specialization_prefix_size(instantiate_rev(f, m_locals.size(), m_locals.data()), args.size());
expr new_f = e;
unsigned rest_sz = args.size() - prefix_sz;
for (unsigned i = 0; i < rest_sz; i++)
new_f = app_fn(new_f);
new_f = instantiate_rev(new_f, m_locals.size(), m_locals.data());
optional<congr_lemma> congr = m_congr_lemma_manager.mk_congr(new_f, rest_sz);
h = hash(new_f);
if (!congr) {
for (unsigned i = prefix_sz; i < args.size(); i++) {
h = ::lean::hash(h, hash(args[i]));
}
} else {
lean_assert(length(congr->get_arg_kinds()) == rest_sz);
unsigned i = prefix_sz;
for_each(congr->get_arg_kinds(), [&](congr_arg_kind const & c_kind) {
if (c_kind != congr_arg_kind::Cast) {
h = ::lean::hash(h, hash(args[i]));
}
i++;
});
}
return h;
}
lean_unreachable();
}
static optional<pair<expr, unsigned>> find_hyp_core(expr const & meta, F && pred) {
expr const * it = &meta;
unsigned i = 0;
while (is_app(*it)) {
expr const & h = app_arg(*it);
if (pred(h))
return some(mk_pair(h, i));
i++;
it = &app_fn(*it);
}
return optional<pair<expr, unsigned>>();
}
static bool is_permutation(expr const & lhs, expr const & rhs, unsigned offset, buffer<optional<unsigned>> & p) {
if (lhs.kind() != rhs.kind())
return false;
switch (lhs.kind()) {
case expr_kind::Constant: case expr_kind::Sort:
case expr_kind::Meta: case expr_kind::Local:
return lhs == rhs;
case expr_kind::Var:
if (var_idx(lhs) < offset) {
return lhs == rhs; // locally bound variable
} else if (var_idx(lhs) - offset < p.size()) {
if (p[var_idx(lhs) - offset]) {
return *(p[var_idx(lhs) - offset]) == var_idx(rhs);
} else {
p[var_idx(lhs) - offset] = var_idx(rhs);
return true;
}
} else {
return lhs == rhs; // free variable
}
case expr_kind::Lambda: case expr_kind::Pi:
return
is_permutation(binding_domain(lhs), binding_domain(rhs), offset, p) &&
is_permutation(binding_body(lhs), binding_body(rhs), offset+1, p);
case expr_kind::App:
return
is_permutation(app_fn(lhs), app_fn(rhs), offset, p) &&
is_permutation(app_arg(lhs), app_arg(rhs), offset, p);
case expr_kind::Macro:
if (macro_def(lhs) != macro_def(rhs) ||
macro_num_args(lhs) != macro_num_args(rhs))
return false;
for (unsigned i = 0; i < macro_num_args(lhs); i++) {
if (!is_permutation(macro_arg(lhs, i), macro_arg(rhs, i), offset, p))
return false;
}
return true;
}
lean_unreachable();
}
expr const & get_app_args_at_most(expr const & e, unsigned num, buffer<expr> & args) {
unsigned sz = args.size();
expr const * it = &e;
unsigned i = 0;
while (is_app(*it)) {
if (i == num)
break;
args.push_back(app_arg(*it));
it = &(app_fn(*it));
i++;
}
std::reverse(args.begin() + sz, args.end());
return *it;
}
expr pack(unsigned i, unsigned arity, buffer<expr> const & args, expr const & type) {
lean_assert(arity > 0);
if (i == arity - 1) {
return args[i];
} else {
lean_assert(is_constant(get_app_fn(type), get_psigma_name()));
expr a = args[i];
expr A = app_arg(app_fn(type));
expr B = app_arg(type);
lean_assert(is_lambda(B));
expr new_type = instantiate(binding_body(B), a);
expr b = pack(i+1, arity, args, new_type);
bool mask[2] = {true, true};
expr AB[2] = {A, B};
return mk_app(mk_app(m_ctx, get_psigma_mk_name(), 2, mask, AB), a, b);
}
}
void collect_locals(expr const & e, collected_locals & ls, bool restricted) {
if (!has_local(e))
return;
expr_set visited;
std::function<void(expr const & e)> visit = [&](expr const & e) {
if (!has_local(e))
return;
if (restricted && is_meta(e))
return;
if (visited.find(e) != visited.end())
return;
visited.insert(e);
switch (e.kind()) {
case expr_kind::Var: case expr_kind::Constant: case expr_kind::Sort:
break; // do nothing
case expr_kind::Local:
if (!restricted)
visit(mlocal_type(e));
ls.insert(e);
break;
case expr_kind::Meta:
lean_assert(!restricted);
visit(mlocal_type(e));
break;
case expr_kind::Macro:
for (unsigned i = 0; i < macro_num_args(e); i++)
visit(macro_arg(e, i));
break;
case expr_kind::App:
visit(app_fn(e));
visit(app_arg(e));
break;
case expr_kind::Lambda:
case expr_kind::Pi:
visit(binding_domain(e));
visit(binding_body(e));
break;
case expr_kind::Let:
visit(let_type(e));
visit(let_value(e));
visit(let_body(e));
break;
}
};
visit(e);
}
unsigned light_lt_manager::get_weight_core(expr const & e) {
switch (e.kind()) {
case expr_kind::Var: case expr_kind::Constant: case expr_kind::Sort:
case expr_kind::Meta: case expr_kind::Local:
return 1;
case expr_kind::Lambda: case expr_kind::Pi:
return safe_add(1, safe_add(get_weight(binding_domain(e)), get_weight(binding_body(e))));
case expr_kind::Macro:
return safe_add(1, add_weight(macro_num_args(e), macro_args(e)));
case expr_kind::App:
buffer<expr> args;
expr fn = get_app_args(e, args);
if (is_constant(fn)) {
unsigned const * light_arg = m_lrs.find(const_name(fn));
if (light_arg && args.size() > *light_arg) return get_weight(args[*light_arg]);
}
return safe_add(1, safe_add(get_weight(app_fn(e)), get_weight(app_arg(e))));
}
lean_unreachable(); // LCOV_EXCL_LINE
}
/** \brief Given l : H, and R == (or ... l ...), create a proof term for R using or_intro_left and or_intro_right */
expr mk_or_intro(expr const & l, expr const & H, expr const & R, extension_context & ctx) const {
check_system("resolve macro");
if (is_or_app(R)) {
expr lhs = app_arg(app_fn(R));
expr rhs = app_arg(R);
// or_intro_left {a : Prop} (H : a) (b : Prop) : a ∨ b
// or_intro_right {b : Prop} (a : Prop) (H : b) : a ∨ b
if (is_def_eq(l, lhs, ctx)) {
return mk_app(*g_or_intro_left, l, H, rhs);
} else if (is_def_eq(l, rhs, ctx)) {
return mk_app(*g_or_intro_right, l, lhs, H);
} else {
return mk_app(*g_or_intro_right, rhs, lhs, mk_or_intro(l, H, rhs, ctx));
}
} else if (is_def_eq(l, R, ctx)) {
return H;
} else {
throw_kernel_exception(ctx.env(), "bug in resolve macro");
}
}
expr apply(expr const & e, unsigned offset) {
bool shared = false;
if (m_use_cache && is_shared(e)) {
if (auto r = m_cache->find(e, offset))
return *r;
shared = true;
}
check_interrupted();
check_memory("replace");
if (optional<expr> r = m_f(e, offset)) {
return save_result(e, offset, *r, shared);
} else {
switch (e.kind()) {
case expr_kind::Constant: case expr_kind::Sort: case expr_kind::Var:
return save_result(e, offset, e, shared);
case expr_kind::Meta: case expr_kind::Local: {
expr new_t = apply(mlocal_type(e), offset);
return save_result(e, offset, update_mlocal(e, new_t), shared);
}
case expr_kind::App: {
expr new_f = apply(app_fn(e), offset);
expr new_a = apply(app_arg(e), offset);
return save_result(e, offset, update_app(e, new_f, new_a), shared);
}
case expr_kind::Pi: case expr_kind::Lambda: {
expr new_d = apply(binding_domain(e), offset);
expr new_b = apply(binding_body(e), offset+1);
return save_result(e, offset, update_binding(e, new_d, new_b), shared);
}
case expr_kind::Macro: {
buffer<expr> new_args;
unsigned nargs = macro_num_args(e);
for (unsigned i = 0; i < nargs; i++)
new_args.push_back(apply(macro_arg(e, i), offset));
return save_result(e, offset, update_macro(e, new_args.size(), new_args.data()), shared);
}}
lean_unreachable();
}
}
bool light_lt_manager::is_lt(expr const & a, expr const & b) {
if (is_eqp(a, b)) return false;
unsigned wa = get_weight(a);
unsigned wb = get_weight(b);
if (wa < wb) return true;
if (wa > wb) return false;
if (is_constant(get_app_fn(a))) {
unsigned const * light_arg = m_lrs.find(const_name(get_app_fn(a)));
if (light_arg) {
buffer<expr> args;
get_app_args(a, args);
if (args.size() > *light_arg) return is_lt(args[*light_arg], b);
}
}
if (is_constant(get_app_fn(b))) {
unsigned const * light_arg = m_lrs.find(const_name(get_app_fn(b)));
if (light_arg) {
buffer<expr> args;
get_app_args(b, args);
if (args.size() > *light_arg) return !is_lt(args[*light_arg], a);
}
}
if (a.kind() != b.kind()) return a.kind() < b.kind();
if (a == b) return false;
switch (a.kind()) {
case expr_kind::Var:
return var_idx(a) < var_idx(b);
case expr_kind::Constant:
if (const_name(a) != const_name(b))
return const_name(a) < const_name(b);
else
return ::lean::is_lt(const_levels(a), const_levels(b), false);
case expr_kind::App:
if (app_fn(a) != app_fn(b))
return is_lt(app_fn(a), app_fn(b));
else
return is_lt(app_arg(a), app_arg(b));
case expr_kind::Lambda: case expr_kind::Pi:
if (binding_domain(a) != binding_domain(b))
return is_lt(binding_domain(a), binding_domain(b));
else
return is_lt(binding_body(a), binding_body(b));
case expr_kind::Sort:
return ::lean::is_lt(sort_level(a), sort_level(b), false);
case expr_kind::Local: case expr_kind::Meta:
if (mlocal_name(a) != mlocal_name(b))
return mlocal_name(a) < mlocal_name(b);
else
return is_lt(mlocal_type(a), mlocal_type(b));
case expr_kind::Macro:
if (macro_def(a) != macro_def(b))
return macro_def(a) < macro_def(b);
if (macro_num_args(a) != macro_num_args(b))
return macro_num_args(a) < macro_num_args(b);
for (unsigned i = 0; i < macro_num_args(a); i++) {
if (macro_arg(a, i) != macro_arg(b, i))
return is_lt(macro_arg(a, i), macro_arg(b, i));
}
return false;
}
lean_unreachable(); // LCOV_EXCL_LINE
}
expr visit_app(expr const & e) {
expr new_f = visit(app_fn(e));
expr new_v = visit(app_arg(e));
return update_app(e, new_f, new_v);
}
bool abstract_expr_manager::is_equal(expr const & a, expr const & b) {
if (is_eqp(a, b)) return true;
if (a.kind() != b.kind()) return false;
if (is_var(a)) return var_idx(a) == var_idx(b);
bool is_eq;
switch (a.kind()) {
case expr_kind::Var:
lean_unreachable(); // LCOV_EXCL_LINE
case expr_kind::Constant: case expr_kind::Sort:
return a == b;
case expr_kind::Meta: case expr_kind::Local:
return mlocal_name(a) == mlocal_name(b) && is_equal(mlocal_type(a), mlocal_type(b));
case expr_kind::Lambda: case expr_kind::Pi:
if (!is_equal(binding_domain(a), binding_domain(b))) return false;
// see comment at abstract_expr_manager::hash
m_locals.push_back(instantiate_rev(m_tctx.mk_tmp_local(binding_domain(a)), m_locals.size(), m_locals.data()));
is_eq = is_equal(binding_body(a), binding_body(b));
m_locals.pop_back();
return is_eq;
case expr_kind::Macro:
if (macro_def(a) != macro_def(b) || macro_num_args(a) != macro_num_args(b))
return false;
for (unsigned i = 0; i < macro_num_args(a); i++) {
if (!is_equal(macro_arg(a, i), macro_arg(b, i)))
return false;
}
return true;
case expr_kind::App:
buffer<expr> a_args, b_args;
expr const & f_a = get_app_args(a, a_args);
expr const & f_b = get_app_args(b, b_args);
if (!is_equal(f_a, f_b))
return false;
if (a_args.size() != b_args.size())
return false;
unsigned prefix_sz = m_congr_lemma_manager.get_specialization_prefix_size(instantiate_rev(f_a, m_locals.size(), m_locals.data()), a_args.size());
for (unsigned i = 0; i < prefix_sz; i++) {
if (!is_equal(a_args[i], b_args[i]))
return false;
}
expr new_f_a = a;
unsigned rest_sz = a_args.size() - prefix_sz;
for (unsigned i = 0; i < rest_sz; i++) {
new_f_a = app_fn(new_f_a);
}
new_f_a = instantiate_rev(new_f_a, m_locals.size(), m_locals.data());
optional<congr_lemma> congr = m_congr_lemma_manager.mk_congr(new_f_a, rest_sz);
bool not_equal = false;
if (!congr) {
for (unsigned i = prefix_sz; i < a_args.size(); ++i) {
if (!is_equal(a_args[i], b_args[i])) {
not_equal = true;
break;
}
}
} else {
lean_assert(length(congr->get_arg_kinds()) == rest_sz);
unsigned i = prefix_sz;
for_each(congr->get_arg_kinds(), [&](congr_arg_kind const & c_kind) {
if (not_equal)
return;
if (c_kind != congr_arg_kind::Cast && !is_equal(a_args[i], b_args[i])) {
not_equal = true;
}
i++;
});
}
return !not_equal;
}
lean_unreachable(); // LCOV_EXCL_LINE
}
expr update_app(expr const & e, expr const & new_fn, expr const & new_arg) {
if (!is_eqp(app_fn(e), new_fn) || !is_eqp(app_arg(e), new_arg))
return mk_app(new_fn, new_arg, e.get_tag());
else
return e;
}
expr replace_visitor::visit_app(expr const & e) {
lean_assert(is_app(e));
return update_app(e, visit(app_fn(e)), visit(app_arg(e)));
}
