pub fn downcast_ref<T: Fail>(&self) -> Option<&T> {
        if self.__private_get_type_id__() == TypeId::of::<T>() {
            unsafe { Some(&*(self as *const dyn Fail as *const T)) }
        } else {
            None
        }
    }
/// Attempts to downcast this failure to a concrete type by reference.
///
/// If the underlying error is not of type `T`, this will return `None`.
Attempts to downcast this failure to a concrete type by reference.
If the underlying error is not of type `T`, this will return `None`.
Attempts to downcast this failure to a concrete type by reference . If the underlying error is not of type ` T ` this will return ` None ` .
pub fn downcast_ref<T: Fail>(&self) -> Option<&T> {
        if self.__private_get_type_id__() == TypeId::of::<T>() {
            unsafe { Some(&*(self as *const dyn Fail as *const T)) }
        } else {
            None
        }
    }
pub fn downcast_ref < T : Fail > ( & self ) -> Option < & T > { if self . __private_get_type_id__ ( ) == TypeId :: of :: < T > ( ) { unsafe { Some ( & * ( self as * const dyn Fail as * const T ) ) } } else { None } }
Attempts to downcast this failure to a concrete type by reference.
Attempts to downcast this failure to a concrete type by reference .
&self
&self