Trait signature::PrehashSignature 
source ยท pub trait PrehashSignature {
    type Digest: Digest;
}Expand description
Marker trait for Signature types computable as ๐(๐(๐))
i.e. ones which prehash a message to be signed as ๐(๐)
Where:
- ๐: signature algorithm
- ๐: hash (a.k.a. digest) function
- ๐: message
This approach is relatively common in signature schemes based on the Fiat-Shamir heuristic.
For signature types that implement this trait, when the derive crate
feature is enabled a custom derive for Signer is available for any
types that impl DigestSigner, and likewise for deriving Verifier for
types which impl DigestVerifier.