/**
* gtk_button_new_from_icon_name:
- * @icon_name: an icon name
+ * @icon_name: (nullable): an icon name or %NULL
* @size: (type int): an icon size (#GtkIconSize)
*
* Creates a new button containing an icon from the current icon theme.
/**
* gtk_gesture_handles_sequence:
* @gesture: a #GtkGesture
- * @sequence: a #GdkEventSequence
+ * @sequence: (nullable): a #GdkEventSequence or %NULL
*
* Returns %TRUE if @gesture is currently handling events corresponding to
* @sequence.
*
- * Returns: %TRUE if @gesture is handling @sequence
+ * Returns: %TRUE if @gesture is handling @sequence, %FALSE otherwise
*
* Since: 3.14
**/
/**
* gtk_image_set_from_surface:
* @image: a #GtkImage
- * @surface: a cairo_surface_t
+ * @surface: (nullable): a cairo_surface_t or %NULL
*
* See gtk_image_new_from_surface() for details.
*