Trait AcceptUpperBound 

pub trait AcceptUpperBound {
    type Output;
    type Eval<const UPPER: usize>: Const<Type = Self::Output>;

    const DESIRED_GENERIC: usize;
}

Allows implementing a callback pattern that accepts an upper bound for a desired generic const parameter.

The trait works by allowing implementors to specify, for each upper bound, a value that is computed from that upper bound. This value is represented as a generic associated type with bound Const, as this is currently the only way to implement a const item with generics in a trait.

When passed to eval_with_upper_bound, Eval::<UPPER>::VALUE will be evaluated with a parameter UPPER that satisfies DESIRED_GENERIC <= UPPER < 2 * DESIRED_GENERIC.

Required Associated Constants

const DESIRED_GENERIC: usize

The desired value and lower bound that the implementor wants to be passed to Self::Eval.

Required Associated Types

type Output

The output type of the evaluation.

type Eval<const UPPER: usize>: Const<Type = Self::Output>

Evals the constant by mapping a generic parameter that is at least the desired value to the output value. const_value::<Eval<UPPER>>() should be indistinguishable for all possible generic parameters passed to this.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors