strafe-project/src/macros/wide.rs

#[doc(hidden)]
#[macro_export(local_inner_macros)]
macro_rules! impl_wide_operations {
    ( $struct: ident { $($field: ident), + }, $size: expr ) => {
	    impl<U,T:Copy+fixed_wide::wide::WideMul<Output=U>> fixed_wide::wide::WideMul for $struct<T> {
			type Output=$struct<U>;
            #[inline]
            fn wide_mul(self, rhs: Self) -> Self::Output {
            	$struct{
                    $( $field: self.$field.wide_mul(rhs.$field) ), +
                }
            }
		}
        impl<T:Copy+fixed_wide::wide::WideMul<Output=T>+std::ops::Add<Output=T>> $struct<T> {
            #[inline]
            pub fn wide_dot(&self, other: &Self) -> <T as fixed_wide::wide::WideMul>::Output {
                $crate::sum_repeating!(
                    $( + (self.$field.wide_mul(other.$field)) ) +
                )
            }
            pub fn length_squared(&self) -> <T as fixed_wide::wide::WideMul>::Output {
                let squared = Self {
                    $( $field: self.$field.wide_mul(self.$field) ), +
                };

                $crate::sum_repeating!(
                    $( + squared.$field ) +
                )
            }
        }
    };
}


// HACK: Allows us to sum repeating tokens in macros.
// See: https://stackoverflow.com/a/60187870/17452730
#[doc(hidden)]
#[macro_export(local_inner_macros)]
macro_rules! sum_repeating {
    ( + $($item: tt) * ) => {
        $($item) *
    };
}