array operations and ranges

[Manu via Digitalmars-d]

On 28 April 2015 at 06:42, John Colvin via Digitalmars-d
<digitalmars-d at puremagic.com> wrote:
> On Monday, 27 April 2015 at 06:52:11 UTC, Manu wrote:
>>
>> On 27 April 2015 at 15:58, Vlad Levenfeld via Digitalmars-d
>> <digitalmars-d at puremagic.com> wrote:
>>>>
>>>> Phobos containers already support the first line, and it would be a
>>>> natural extension to make them support the second.
>>>
>>>
>>>
>>> Sure, it's not complicated. It's something I had done in this other code
>>> and
>>> showing for example.
>>
>>
>>
>> Yeah, see I don't feel making a simple thing like an array into
>> something more complex by wrapping it in templates is ever a good
>> thing to do.
>> I just think it's a missed opportunity that the compiler doesn't
>> support any of this in the language.
>>
>> It would appear at face value to be a great opportunity for lowering.
>> Assignment can lower to .copy(), operators can lower to map!(...)
>
>
> builtin slicesopSliceAssign (and opSliceOpAssign) understanding ranges as
> source operands is a good idea. I might even see if I can implement it.
>
> Lowering array operations to lazy ranges seems like a huge can of worms. Not
> so keen. Lazy array ops are great, but I don't see it working out as a
> builtin feature unless it had it's own syntax.

The only reason I considered it workable was because an operator
expression is generally meaningless without an assignment to the left;
"a[] = b[]*2;", so the mul could conceivably be expressed in a lazy
sense, since it will be evaluated immediately by the assignment.

Array operations passed as arguments to functions are already not
allowed in the usual case, so I think it would be fine in this
instance... it's impossibly for an array operation to have any meaning
without a final assignment (I think?)