//deeply nested closure with destructive assignment
fn makemakecounter(){
    let makecounter = | |{
        let x = 0.0
        let countup = | |{
            let res = x
            x = x+1.0
            res 
        }
        countup
    }
    makecounter
}
let mymc = makemakecounter();
let myc = mymc();
fn dsp(){
    myc()
}