Unchecked Counter [![Foundry][foundry-badge]][foundry] [![License: MIT][license-badge]][license]

[foundry]: https://getfoundry.sh/
[foundry-badge]: https://img.shields.io/badge/Built%20with-Foundry-FFDB1C.svg
[license]: https://opensource.org/licenses/MIT
[license-badge]: https://img.shields.io/badge/License-MIT-blue.svg

Solidity counter type that bypasses checked arithmetic, designed to be used in for loops.

Background

User-defined value types (UDVTs) provide a means to create aliases for elementary Solidity types, resulting in a
zero-cost abstraction that enhances type safety and improves code readability. Solidity v0.8.19 onwards allows for the
binding of operators such as + to UDVTs, making the syntax even more concise and expressive.

Further recommended reading on this topic:

- Solidity v0.8.8: User-Defined Value Types
- Solidity v0.8.19: User-Defined Operators

Install

``sh
forge install PaulRBerg/unchecked-counter@v1
`

Your .gitmodules file should now contain the following entry:

`toml
[submodule "lib/unchecked-counter"]
branch = "v1"
path = "lib/unchecked-counter"
url = "https://github.com/PaulRBerg/unchecked-counter"
`

Usage

$3

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

import { UC, uc } from "unchecked-counter/UC.sol";

// Example that uses the uc casting function
function iterate(uint256[] memory arr) pure {
for (UC i = uc(0); i < uc(100); i = i + uc(1)) {
uint256 element = arr[i.into()]; // or i.unwrap()
}
}

`

$3

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

import { ONE, UC, ZERO } from "unchecked-counter/UC.sol";

// Example that uses the constants ONE and ZERO
function iterate(uint256[] memory arr) pure {
uint256 counter;
for (UC i = uc(0); i < uc(100); i = i + uc(1)) {
uint256 element = arr[i.into()]; // or i.unwrap()
}
}
`

Contributing

Feel free to dive in! Open an issue,
start a discussion or submit a PR.

$3

You will need the following software on your machine:

- Git
- Foundry
- Node.Js
- Yarn

In addition, familiarity with Solidity is requisite.

$3

Clone this repository including submodules:

`sh
$ git clone --recurse-submodules -j8 git@github.com:PaulRBerg/unchecked-counter.git
`

Then, inside the project's directory, run this to install the Node.js dependencies:

`sh
$ yarn install
``

Now you can start making changes.

License

MIT © Paul Razvan Berg