Function require_attenuated 

pub fn require_attenuated(
    child: &GrantSet,
    parent: &GrantSet,
) -> Result<(), Refusal>

Require that child is within parent — the Law I attenuation check.

Errors

Returns Refusal::Widened when a child atom is proved to escape, and Refusal::UndecidableContainment when it merely cannot be proved not to. Both are refusals: an undecided comparison never passes.