David Stone wrote:

The one main design decision for a multi-dimensional array is what begin() and end() iterate over: int, or array?

They iterate over int[4][5] in my suggestion. This is, admittedly, not a "true" multidimensional array, it's just how C arrays work. int a[3][4][5]; for( auto& x: a ) { // x is int (&)[4][5] here } This is consistent with begin() returning T* == int(*)[4][5] and op[] returning T& == int(&)[4][5].

On 05/06/2015 04:01 PM, Brian Smith wrote:

On 5/6/15, Peter Dimov wrote:

...

Currently, creating a multidimensional boost/std::array is a bit unwieldy:

array, 4>, 3> a; // int a[3][4][5] a[2][3][4] = 5;

As a first step, we should consider enabling the element type T of array

N> to be an array type.

array a; // int a[3][4][5] a[2][3][4] = 5;

This almost works already, except for the array interface functions specified and implemented in terms of, say, std::equal or std::fill.

It is an open question whether these standard algorithms should not be fixed

themselves to work on array types, as swap_ranges has been, but for now, we

can implement the array functions in a way that works.

Opinions on that part?

If we agree that this is a good idea, the next logical step would be to eliminate the special handling of the first extent and simply allow

array a; // int a[3][4][5] a[2][3][4] = 5;

There's a multidimensional array submitted for review at https://github.com/BrianJSmith/Array. The syntax is array

...

, iteration is over each dimension, if that would suit your needs.

Brian

+1 I'm curious about this also. Larry