@[inline]

def ReaderT.orElse {m : Type u_1 → Type u_2} {ρ α : Type u_1} [Alternative m] (x₁ : ReaderT ρ m α) (x₂ : Unit → ReaderT ρ m α) : ReaderT ρ m α

Recovers from errors. The same local value is provided to both branches. Typically used via the <|> operator.

@[inline]

def ReaderT.failure {m : Type u_1 → Type u_2} {ρ α : Type u_1} [Alternative m] : ReaderT ρ m α

Fails with a recoverable error.

instance ReaderT.instAlternativeOfMonad {m : Type u_1 → Type u_2} {ρ : Type u_1} [Alternative m] [Monad m] : Alternative (ReaderT ρ m)

instance instMonadControlReaderT {m : Type u_1 → Type u_2} {ρ : Type u_1} : MonadControl m (ReaderT ρ m)

@[always_inline]

instance ReaderT.tryFinally {m : Type u_1 → Type u_2} {ρ : Type u_1} [MonadFinally m] : MonadFinally (ReaderT ρ m)

@[reducible]

def ReaderM (ρ α : Type u) : Type u

A monad with access to a read-only value of type ρ. The value can be locally overridden by withReader, but it cannot be mutated.