Safe Haskell	None
Language	Haskell2010

Ouroboros.Consensus.HardFork.Combinator.Protocol.ChainSel

Description

Infrastructure for doing chain selection across eras

Synopsis

data AcrossEraMode (cfg ∷ Type → Type) a where
- AcrossEraCompare ∷ AcrossEraMode (Proxy ∷ Type → Type) Ordering
- AcrossEraPreferCandidate ∷ AcrossEraMode WrapChainOrderConfig Bool
data AcrossEraSelection a b where
- CompareBlockNo ∷ ∀ a b. AcrossEraSelection a b
- CompareSameSelectView ∷ ∀ a b. SelectView (BlockProtocol a) ~ SelectView (BlockProtocol b) ⇒ AcrossEraSelection a b
data WithBlockNo (f ∷ k → Type) (a ∷ k) = WithBlockNo {
- getBlockNo ∷ BlockNo
- dropBlockNo ∷ f a
}
acrossEraSelection ∷ ∀ (xs ∷ [Type]) (cfg ∷ Type → Type) a. All SingleEraBlock xs ⇒ AcrossEraMode cfg a → NP cfg xs → Tails AcrossEraSelection xs → WithBlockNo (NS WrapSelectView) xs → WithBlockNo (NS WrapSelectView) xs → a
mapWithBlockNo ∷ ∀ {k1} {k2} f (x ∷ k1) g (y ∷ k2). (f x → g y) → WithBlockNo f x → WithBlockNo g y

Documentation

data AcrossEraMode (cfg ∷ Type → Type) a where Source #

GADT indicating whether we are lifting compare or preferCandidate to the HFC, together with the type of configuration we need for that and the result type.

Constructors

AcrossEraCompare ∷ AcrossEraMode (Proxy ∷ Type → Type) Ordering
AcrossEraPreferCandidate ∷ AcrossEraMode WrapChainOrderConfig Bool

data AcrossEraSelection a b where Source #

Constructors

CompareBlockNo ∷ ∀ a b. AcrossEraSelection a b

Just compare block numbers

This is a useful default when two eras run totally different consensus protocols, and we just want to choose the longer chain.

CompareSameSelectView ∷ ∀ a b. SelectView (BlockProtocol a) ~ SelectView (BlockProtocol b) ⇒ AcrossEraSelection a b

Two eras using the same SelectView. In this case, we can just compare chains even across eras, as the chain ordering is fully captured by SelectView and its ChainOrder instance.

We use the ChainOrderConfig of the SelectView in the newer era (with the intuition that newer eras are generally "preferred") when invoking compareChains. However, this choice is arbitrary; we could also make it configurable here.

data WithBlockNo (f ∷ k → Type) (a ∷ k) Source #

Constructors