coolmacrobro.rs

use paste::paste;

macro_rules! dispatch_trait_fn {
    ($value_name:ident : $value:ty => $key_name:ident : $key:ty) => {
        paste!(
            fn [<get_ $value_name>](&self, $key_name:$key) -> Result<$value>; 
            fn [<put_ $value_name>](&self, $value_name:$value) -> Result<$key>; 
        );
    }
}

trait ChainState { 
    // fn get_block(&self, hash: Sha256Bytes) -> Option<Block>;
    // fn put_block(&self, block: Block) -> Result<Sha256Bytes>;
    dispatch_trait_fn!(block: Block => hash: Sha256Bytes);
    dispatch_trait_fn!(account: Account => hash: Sha256Bytes);
}

// get_deserialize(hash => Account)
// Account::try_from_slice(
//     db.get(account_digest)?.unwrap().as_slice()
// )?
macro_rules! get {
    ($db:expr, $input:ident => $value:ty) => {
        Ok(<$value>::try_from_slice( 
            $db.get($input)?.unwrap().as_slice()
        )?)
    };
}
              
struct RocksDB { 
    db: DB
}
             
impl ChainState for RocksDB { 
    fn get_account(&self, hash:Sha256Bytes) -> Result<Account> {
        get!(self.db, hash => Account) 
    }
}