[−][src]Trait ensure::Existential
Existential types are types that can ensure Present<T>
or Absent<T>
states for External
type T
.
Associated Types
type Error
Required methods
fn ensure_present(self) -> Result<Present<T>, Self::Error>
Ensure that T
is Present<T>
fn ensure_absent(self) -> Result<Absent<T>, Self::Error>
Ensure that T
is Absent<T>
Implementors
impl<T, E, R, PA, AA> Existential<T> for R where
R: Ensure<Present<T>, EnsureAction = PA>,
PA: Meet<Met = Present<T>, Error = E>,
R: Ensure<Absent<T>, EnsureAction = AA>,
AA: Meet<Met = Absent<T>, Error = E>,
T: External,
[src]
R: Ensure<Present<T>, EnsureAction = PA>,
PA: Meet<Met = Present<T>, Error = E>,
R: Ensure<Absent<T>, EnsureAction = AA>,
AA: Meet<Met = Absent<T>, Error = E>,
T: External,
Types implement Existential
trait if they implement both Ensure<Present<T>>
and Ensure<Absent<T>>
.