Macro to generate Input combinations

macro.rs

macro_rules! create_input_tracker {
    ($name: ident, $( $element: ident: $ty: ty ; $text: tt ) , +) => {
        /// A simple combination of input trackers.
        ///
        /// You can use this as your [`Game::Input`] directly!
        ///
        /// [`Game::Input`]: ../trait.Game.html#associatedtype.Input
        pub struct $name {
            $ (
                $element: $ty,
            ) +
        }

        impl $name {
            $ (
                #[doc = "Returns the "]
                #[doc = $text]
                #[doc = " input tracker."]
                pub fn $element(&self) -> &$ty {
                    &self.$element
                }
            ) +
        }

        impl Input for $name {
            fn new() -> $name {
                $name {
                    $ (
                        $element: <$ty as Input>::new(),
                    ) +
                }
            }

            fn update(&mut self, event: Event) {
                $ (
                    <$ty as Input>::update(&mut self.$element, event);
                ) +
            }

            fn clear(&mut self) {
                $ (
                    <$ty as Input>::clear(&mut self.$element);
                ) +
            }
        }
    };
}

create_input_tracker!(KeyboardAndMouse, mouse: Mouse; "mouse", keyboard: Keyboard; "keyboard");