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extend_form_class(options, default_classes)

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Extends Phoenix.HTML.Form.form_for/3 options to merge css class as with PhxComponentHelpers.extend_class/2.

It's useful to define your own form_for functions with default css classes that still can be overriden from the template.


def my_form_for(form_data, action, options) when is_list(options) do
  new_options = extend_form_class(options, "mt-4 space-y-2")
  form_for(form_data, action, new_options)