tuple can write [],but can't read []

[FrankLike via Digitalmars-d]

On Tuesday, 29 April 2014 at 09:38:45 UTC, Andrea Fontana wrote:
> On Tuesday, 29 April 2014 at 09:23:03 UTC, FrankLike wrote:
>> Hi,erveryone,
>> [...]
>> 	xy2[1][0]=100;  // can write
>> [...]
>> 	writeln(xy2[0][i]); //  can't read
>> [...]
>
> If I'm right, index should be a compile-time value.

index is exists,but not be read,why?

Thank you.