@[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.

Equations

• x₁.orElse x₂ s = (x₁ s <|> x₂ () s)

@[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.

Equations

• ReaderT.failure x✝ = failure

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

Equations

• ReaderT.instAlternativeOfMonad = { toApplicative := ReaderT.instApplicativeOfMonad, failure := fun {α : Type ?u.23} => ReaderT.failure, orElse := fun {α : Type ?u.23} => ReaderT.orElse }

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

Equations

• One or more equations did not get rendered due to their size.

@[always_inline]

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

Equations

• ReaderT.tryFinally = { tryFinally' := fun {α β : Type ?u.24} (x : ReaderT ρ m α) (h : Option α → ReaderT ρ m β) (ctx : ρ) => tryFinally' (x ctx) fun (a? : Option α) => h a? ctx }

@[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.

Equations

• ReaderM ρ = ReaderT ρ Id