Enum ValueSize 

pub enum ValueSize<'v, ValueType> {
    Const(usize),
    Variable(&'v dyn Fn(&ValueType) -> usize),
}

Points the number of bytes needed to store value of the type ValueType. This number of bytes can be constant or can depend on the value.

Variants

Const(usize)

Holds constant number of bytes needed to store each value.

Variable(&'v dyn Fn(&ValueType) -> usize)

Holds callback that shows the number of bytes needed to store given value.