/// Counts number of elements.
////// It's used in other macros.
////// # Examples
////// ```
/// # pub use assessment::count;
/// assert_eq!(count![3 "a" 5.7], 3);
/// ```
///#[macro_export]macro_rules!count{()=>(0usize);($x:tt$($xs:tt)*)=>(1usize+$crate::count!($($xs)*));}