code: func (v *Scrollable) GetHAdjustment() (*Adjustment, error) {
  	c := C.gtk_scrollable_get_hadjustment(v.native())
  	if c == nil {
  		return nil, nilPtrErr
  	}
  	return wrapAdjustment(glib.Take(unsafe.Pointer(c))), nil
  }
docs: // GetHAdjustment is a wrapper around gtk_scrollable_get_hadjustment().