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();
});
}
name get_unused_name(name const & prefix, unsigned & idx, buffer<expr> const & locals) {
while (true) {
name curr = prefix.append_after(idx);
idx++;
if (!uses_name(curr, locals))
return curr;
}
}
static name mk_fresh_name(environment const & env, buffer<name> const & names, name const & s) {
unsigned i = 1;
name c = s;
while (true) {
if (!env.find(c) &&
std::find(names.begin(), names.end(), c) == names.end())
return c;
c = s.append_after(i);
i++;
}
}
name mk_name_for(expr const & e) {
lean_assert(is_nested_declaration(e));
if (auto n = get_nested_declaration_name(e)) {
return *n;
} else {
name ns = get_namespace(m_env);
while (true) {
name aux = m_dname.append_after(m_idx);
m_idx++;
if (!m_env.find(ns + aux))
return aux;
}
}
}