use crateMapper;
/// visit Collectable and get result
///
/// Mapper may used when reach the end of iterating when there no next should be given
/// to help Collector and get result
///
/// use collector to iterate values in it
/*
impl<Input,Next,Output,TFn:Fn(Input,Next)->Output> Collector<Input,Next> for TFn {
type Output=Output;
fn collect(self,value:Input,next:Next)-><Self as Collector<Input,Next>>::Output {
}
} */