def guard_null(context, builder, value, exc_tuple):
 with builder.if_then(is_scalar_zero(builder, value), likely=False):
  exc = exc_tuple[0]
  exc_args = (exc_tuple[1:] or None)
  context.call_conv.return_user_exc(builder, exc, exc_args)

def guard_null ( context , builder , value , exc_tuple ) : with builder . if_then ( is_scalar_zero ( builder , value ) , likely = False ) : exc = exc_tuple [ 0 ] exc_args = ( exc_tuple [ 1 : ] or None ) context . call_conv . return_user_exc ( builder , exc , exc_args )
guard against *value* being null or zero .