On Tue, Mar 06, 2012 at 09:35:11PM +0100, Timon Gehr wrote:
> On 03/06/2012 09:30 PM, H. S. Teoh wrote:
> >It'd be really cool if I could do this:
> >
> >	void func(int[] vector, int[] bounds) {
> >		assert(vector[]>= 0&&  vector[]<  bounds[]);
> >		...
> >	}
> >
> >Is there any reason why we shouldn't implement this?
[...]
> 
> Comparing arrays already does lexical-style comparison (which makes sense).

What I wanted is not lexicographic comparison, but per-element comparison:

	v[]>=0   means  v[0]>0 && v[1]>0 && v[2]>0 && ...
	v[]<b[]  means  v[0]<b[0] && v[1]<b[1] && v[2]<b[2] && ...

as opposed to lexicographical:

	v < b  means  (v[0]!=b[0]) ? v[0]<b[0] :
			(v[1]!=b[1]) ? v[1]<b[1] :
			(v[2]!=b[2]) ? v[2]<b[2] :
			...


T

-- 
This is not a sentence.

On 03/06/2012 09:58 PM, H. S. Teoh wrote:
> On Tue, Mar 06, 2012 at 09:35:11PM +0100, Timon Gehr wrote:
>> On 03/06/2012 09:30 PM, H. S. Teoh wrote:
>>> It'd be really cool if I could do this:
>>>
>>> 	void func(int[] vector, int[] bounds) {
>>> 		assert(vector[]>= 0&&   vector[]<   bounds[]);
>>> 		...
>>> 	}
>>>
>>> Is there any reason why we shouldn't implement this?
> [...]
>>
>> Comparing arrays already does lexical-style comparison (which makes sense).
>
> What I wanted is not lexicographic comparison, but per-element
> comparison:
>
> 	v[]>=0   means  v[0]>0&&  v[1]>0&&  v[2]>0&&  ...
> 	v[]<b[]  means  v[0]<b[0]&&  v[1]<b[1]&&  v[2]<b[2]&&  ...
>
> as opposed to lexicographical:
>
> 	v<  b  means  (v[0]!=b[0]) ? v[0]<b[0] :
> 			(v[1]!=b[1]) ? v[1]<b[1] :
> 			(v[2]!=b[2]) ? v[2]<b[2] :
> 			...
>
>
> T
>

I know. You asked for reasons why it shouldn't be implemented. The main reason is that it is already valid code with different semantics.