[phobos] std.array.ilength

[Walter Bright]

I agree with Andrei.

My more general concern is that if we pump up Phobos with lots of little 
functions and aliases, we get a very large but not very useful library. 
We also increase the "cognitive load" of anyone attempting to understand 
standard D code.

When a standard library feature consists of 3 lines of trivial 
implementation, and 8 lines of documentation, that's a red flag to me 
that it shouldn't be in the library.

I'd really like to see library modules with small api's and large depth 
to them, like an XML parser.