Function sc_consensus_aura::standalone::find_pre_digest

pub fn find_pre_digest<B: BlockT, Signature: Codec>(
    header: &B::Header
) -> Result<Slot, PreDigestLookupError>

Extract a pre-digest from a block header.

This fails if there is no pre-digest or there are multiple.

Returns the slot stored in the pre-digest or an error if no pre-digest was found.