expr apply(expr const & a) {
auto r = m_cache.find(a);
if (r != m_cache.end()) {
lean_assert((*r).raw()->max_shared());
return *r;
}
if (a.raw()->max_shared()) {
m_cache.insert(a);
return a;
}
switch (a.kind()) {
case expr_kind::Var: case expr_kind::Constant: case expr_kind::Type: case expr_kind::Value:
cache(a);
return a;
case expr_kind::App: {
expr r = update_app(a, [=](expr const & c){ return apply(c); });
cache(r);
return r;
}
case expr_kind::Eq : {
expr r = update_eq(a, [=](expr const & l, expr const & r){ return std::make_pair(apply(l), apply(r)); });
cache(r);
return r;
}
case expr_kind::Lambda:
case expr_kind::Pi: {
expr r = update_abst(a, [=](expr const & t, expr const & b) { return std::make_pair(apply(t), apply(b)); });
cache(r);
return r;
}
case expr_kind::Let: {
expr r = update_let(a, [=](expr const & t, expr const & v, expr const & b) {
expr new_t = t ? apply(t) : expr();
return std::make_tuple(new_t, apply(v), apply(b));
});
cache(r);
return r;
}
case expr_kind::MetaVar: {
expr r = update_metavar(a, [=](meta_entry const & e) -> meta_entry {
if (e.is_inst())
return mk_inst(e.s(), apply(e.v()));
else
return e;
});
cache(r);
return r;
}}
lean_unreachable();
}
expr apply(expr const & a) {
bool sh = false;
if (is_shared(a)) {
auto r = m_cache.find(a.raw());
if (r != m_cache.end())
return r->second;
sh = true;
}
switch (a.kind()) {
case expr_kind::Var: case expr_kind::Constant: case expr_kind::Type: case expr_kind::Value:
return save_result(a, copy(a), sh);
case expr_kind::App: {
buffer<expr> new_args;
for (expr const & old_arg : args(a))
new_args.push_back(apply(old_arg));
return save_result(a, mk_app(new_args), sh);
}
case expr_kind::HEq: return save_result(a, mk_heq(apply(heq_lhs(a)), apply(heq_rhs(a))), sh);
case expr_kind::Pair: return save_result(a, mk_pair(apply(pair_first(a)), apply(pair_second(a)), apply(pair_type(a))), sh);
case expr_kind::Proj: return save_result(a, mk_proj(proj_first(a), apply(proj_arg(a))), sh);
case expr_kind::Lambda: return save_result(a, mk_lambda(abst_name(a), apply(abst_domain(a)), apply(abst_body(a))), sh);
case expr_kind::Pi: return save_result(a, mk_pi(abst_name(a), apply(abst_domain(a)), apply(abst_body(a))), sh);
case expr_kind::Sigma: return save_result(a, mk_sigma(abst_name(a), apply(abst_domain(a)), apply(abst_body(a))), sh);
case expr_kind::Let: return save_result(a, mk_let(let_name(a), apply(let_type(a)), apply(let_value(a)), apply(let_body(a))), sh);
case expr_kind::MetaVar:
return save_result(a,
update_metavar(a, [&](local_entry const & e) -> local_entry {
if (e.is_inst())
return mk_inst(e.s(), apply(e.v()));
else
return e;
}),
sh);
}
lean_unreachable(); // LCOV_EXCL_LINE
}
