Uniswap core requires solidity 5 while periphery requires 6

Question

Working through the examples of uniswap v2 (https://uniswap.org/docs/v2/smart-contract-integration/quick-start/) I got stuck with the following problem:

As we can see, v2-core requires solidity 5 while v2-peryphery requires solidity 6.

The issue is opened on the github: https://github.com/Uniswap/uniswap-v2-core/issues/105 from 2020.

Does anyone have a solution to that? How should i import both core and periphery contracts into my contract to make their examples work?

Answer 1

That's one of the... interesting aspects of Uniswap V2. Uniswap really isn't very friendly to cloning.

You have a few options:

1. Use something like Hardhat, which supports multiple Solidity versions in the same project. Also, unless I totally misremember, the newest Truffle also supports multiple versions - or maybe it was just a near future plan, can't really remember.

2. Run them in separate projects

3. Update the core files manually to 0.6.x. Not a fun thing to do.