verify function visibility should be public to enable inheritance

[Turupawn]

Hello, I'm writing educational content about Noir in spanish and @critesjosh has been guiding me on the process. I stumbled into following issue while writing a guide on how to create a dApp. I got redirected here from acvm-backend-barretenberg.

I did a PR #23 that solves this. Happy to hear your comments.

The problem

It should be common for devs to inherit from UltraVerifier while creating a dApp. This is to keep the codebase organized and readable. A normal implementation should look like the following example:

//SPDX-License-Identifier: MIT
pragma solidity >=0.8.19;

contract MyDApp is UltraVerifier {
    // Custom logic
    function proveStuff(bytes calldata _proof, bytes32[] calldata _publicInputs) public {
        verify(_proof, _publicInputs));
        // More custom logic
    }
}

However this is currently not possible due to the verify function being external. This means that this function is not visible to inherited contracts.

The solution

I think the verify visibility should be changed to public. This will enable verify being called from inherited contracts like the example above.

[Maddiaa0]

As mentioned here: #23 (comment) we purposely have the verifier calls as external library calls to ensure that they are writing into clean memory.

The solution should be to swap the contract syntax to be a library instead, we will get this updated within noir

The resulting syntax when the verifier is a library should be something like this:

import {UltraVerifier} from "...path...";

contract MyDApp  {
    // Custom logic
    function proveStuff(bytes calldata _proof, bytes32[] calldata _publicInputs) public {
        UltraVerifier.verify(_proof, _publicInputs));
        // More custom logic
    }
}

[Turupawn]

Noted 📝 , yeah a library would be nice. I'll stick with interfaces for the mean time. Thanks for the explanation!