Addresses

[joneskm]

No description provided.

[NYBACHOK]

Newtype pattern instead of simple type alias?

[joneskm]

What benefits do we get from using the Newtype pattern?

[NYBACHOK]

pub struct BaseAddress<const PREFIX: u8>(Vec<u8>);  

pub struct  AccAddress(  BaseAddress<0> );

impl BaseAddress
{
pub fn from_bech32(address: &str, prefix : u32 ) -> Result<Self, AddressError> {
        let (hrp, data, variant) = bech32::decode(address)?;

// This code could be removed
 //let prefix = if PREFIX == 0 {
//            BECH_32_PREFIX_ACC_ADDR
//        } else {
//            BECH_32_PREFIX_VAL_ADDR
//        };

     if hrp != prefix {
            return Err(AddressError::InvalidPrefix {
                expected: prefix.into(),
                found: hrp,
            });
        };
 // I omitted other code
}


impl AccAddress
{
 pub fn from_bech32(address: &str, ) -> Result<Self, AddressError> {
  Self ( BaseAddress::from_bech32( address, BECH_32_PREFIX_ACC_ADDR )
 }
}

Unsure about other parts of code, but this one method may be simpler.

[joneskm]

We would need to do the same for the ValAddress and for the other public methods of AccAddress.

Once more complex const parameter types arrive in Rust, we'll be able to replace u8 with &'static str, see rust-lang/rust#95174. This will allow for much cleaner code, something like:

pub type AccAddress = BaseAddress<BECH_32_PREFIX_ACC_ADDR>;
pub type ValAddress = BaseAddress<BECH_32_PREFIX_VAL_ADDR>;

#[derive(Debug, PartialEq, Clone)]
pub struct BaseAddress<const PREFIX: &'static str>(Vec<u8>);

impl<const PREFIX: &'static str> BaseAddress<PREFIX> {
    pub fn from_bech32(address: &str) -> Result<Self, AddressError> {
        let (hrp, data, variant) = bech32::decode(address)?;

        // This could be removed
        // let prefix = if PREFIX == 0 {
        //     BECH_32_PREFIX_ACC_ADDR
        // } else {
        //     BECH_32_PREFIX_VAL_ADDR
        // };


        if hrp != PREFIX {
            return Err(AddressError::InvalidPrefix {
                expected: PREFIX.into(),
                found: hrp,
            });
        };

I guess there's two questions:

1. Do we prefer the future const generic method using stror the newtype method?
2. In the meantime which method should we use?

[NYBACHOK]

pub type AccAddress = BaseAddress<BECH_32_PREFIX_ACC_ADDR>;
pub type ValAddress = BaseAddress<BECH_32_PREFIX_VAL_ADDR>;

Looks much better. I didn't think about it.

1. Depends on how quick this feature will arrive and MSV policy.
2. Is it really important to use str over [u8]? If yes, then newtype

[joneskm]

IMO we should use const generics even though we are forced to use a u8