void main()

{

    import std.algorithm.comparison : cmp;

    static bool lessThanCaseInsensitive(size_t a, size_t b)

    {

        import std.ascii : toUpper;

        return toUpper(cast(dchar) a) < toUpper(cast(dchar) b);

    }

    static assert(cmp!lessThanCaseInsensitive("apple2", "APPLE1") != 0,

                 "These are clearly not the same!");

}