# Functions
NewFilter creates a filter that returns if a fork ID should be rejected or not based on the local chain's status.
NewID calculates the Ethereum fork ID from the chain config, genesis hash, head and time.
NewIDWithChain calculates the Ethereum fork ID from an existing chain instance.
NewStaticFilter creates a filter at block zero.
# Variables
ErrLocalIncompatibleOrStale is returned by the validator if a remote fork checksum does not match any local checksum variation, signalling that the two chains have diverged in the past at some point (possibly at genesis).
ErrRemoteStale is returned by the validator if a remote fork checksum is a subset of our already applied forks, but the announced next fork block is not on our already passed chain.
# Interfaces
Blockchain defines all necessary method to build a forkID.
# Type aliases
Filter is a fork id filter to validate a remotely advertised ID.