Function memselect::new1

pub fn new1<A1, I1, F, R>(
    input1: I1, 
    selector: F
) -> impl Selector1<A1, Output = R> where
    F: FnMut(&I1::Output) -> R,
    I1: Selector1<A1>,
    I1::Output: Clone + Eq,
    R: Clone, 

Creates a new memoizing selector with a single input function.

If the return value of input1 doesn't change, selector will not be reinvoked and a cached copy of the result will be returned instead.