backdrop_get_form in core/includes/form.inc

Returns a renderable form array for a given form ID.

drupal_build_form in core/includes/drupal.inc

Builds and processes a form for a given form ID.

form_test_wrapper_callback in core/modules/simpletest/tests/form_test.module

Menu callback; Invokes a form builder function with a wrapper callback.

install_run_task in core/includes/install.core.inc

Runs an individual installation task.

views_ajax_form_wrapper in core/modules/views/includes/ajax.inc

Wrapper around backdrop_build_form to handle some AJAX stuff automatically. This makes some assumptions about the client.

views_plugin_exposed_form::render_exposed_form in core/modules/views/plugins/views_plugin_exposed_form.inc

Render the exposed filter form.

views_ui_ajax_get_form in core/modules/views_ui/views_ui.module

Menu callback; handles AJAX form submissions similar to ajax_form_callback(), but can be used for uncached forms.

views_ui_build_preview in core/modules/views_ui/views_ui.admin.inc