sui

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Trying out a new style of math support. Want to align on the API's we should provide for each integer type first, then we can create similar modules for the other integer types.

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Name	Status	Preview	Comments	Updated
wallet-adapter	❌ Failed (Inspect)			Dec 13, 2022 at 1:20AM (UTC)

muldiv would also be nice to have. I use it a lot in my modules (and copy paste it every time).

/// Calculates (a * b) / c. Aborts if the result doesn't fit into u64.
fun muldiv(a: u64, b: u64, c: u64): u64 {
    (((a as u128) * (b as u128)) / (c as u128) as u64)
}

It preserves precision when you're doing (a * b) / c where a * b doesn't fit into u64 but (a * b) / c does, which I found to be quite often (notice it's applicable any time you have (a / c) * b or a * (b / c), i.e. any time a / c or b / c < 1 e.g. when taking a percentage of something). See this for some real life usages.

Btw there's a really cool way to calculate u256 muldiv using only u256 registers with math tricks: https://2π.com/21/muldiv/

This PR is stale because it has been open 60 days with no activity. Remove stale label or comment or this will be closed in 7 days.

Closing as stale. Raised some of the questions from here internally.