how to sign a msg hash instead of msg with rust bindings?

[zhiqiangxu]

It's not crystally clear from the signatures alone here:

pub fn sign(
                &self,
                msg: &[u8],
                dst: &[u8],
                aug: &[u8],
            )

The golang version is much clearer and can be tuned here:

    if useHash {
        q = HashToG2(msg, dst, augSingle)
    } else {
        q = EncodeToG2(msg, dst, augSingle)
    }

How to make sign do EncodeToG2 instead of HashToG2 in rust?

[dot-asm]

Apparently there is no way. Rust bindings were originally put together with specific applications in mind, and I guess it wasn't originally a concern. And it wasn't an issue so far... Is it a general question or is there actual requirement for it?

[zhiqiangxu]

@dot-asm For me, this is a genuine requirement. I'm somewhat surprised that the API differs between Go and Rust.

[dot-asm]

I fail to interpret the response unambiguously. It sill sounds more like a general question,as if you personally are genuinely surprised there is a difference. Is there an actual requirement in form of a protocol specification?