chooseAmong

auto chooseAmong(Ranges...)(size_t index,  return  scope  Ranges rs) if (Ranges.length >=  2
        &&  allSatisfy!(isInputRange,  staticMap!(Unqual,  Ranges))
         && !is(CommonType!(staticMap!(ElementType,  Ranges))  ==  void))

Choose one of multiple ranges at runtime.

The ranges may be different, but they must have compatible element types. The result is a range that offers the weakest capabilities of all Ranges.

Parameters

`index`	which range to choose, must be less than the number of ranges
`rs`	two or more ranges

Returns

The indexed range. If rs consists of only one range, the return type is an

alias of that range's type.