Type Definition nebari::tree::CompareSwapFn

pub type CompareSwapFn<'a, T, Index> = dyn FnMut(&ArcBytes<'a>, Option<&Index>, Option<T>) -> KeyOperation<T> + 'a;

A function that is allowed to check the current value of a key and determine how to operate on it. The first parameter is the key, and the second parameter is the current value, if present.