How do I tell Twig not to print any form field?

Question

I am trying to theme a form in Drupal 8.

This is the template that I am using which is basically from form.html.twig

<form{{ attributes }}>
{{ element.app_theme_settings }}
{{ element.a2 }}
{{ element.a3 }}

 {% print remaining required form fields. %}
 {{ children }}
</form> 

My problem is I want to print children variable but without app_theme_settings, a2 and a3 children. In Drupal 7 we could use unset function, but in twig I am not sure what to use. I know I can use without filter, but it does not accept the array argument so I have to write name of each element already printed.

 {{ children|without('app_theme_settings','a2','a3' }}

How can I print children without specifying the name of each field one by one?

Answer 1

Loop through the keys

{% for key in element|keys %}
    {{ children|without(key) }}
{% endfor %}