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[Andrei Alexandrescu]

Steven Schveighoffer wrote:
> "Andrei Alexandrescu" wrote
>> Sergey Gromov wrote:
>>> Fri, 10 Oct 2008 08:22:10 -0500,
>>> Andrei Alexandrescu wrote:
>>>> Sergey Gromov wrote:
>>>>> My T[] is useful when you want to recursively split a megabyte file 
>>>>> into a couple thousands of tokens, and then modify some of those 
>>>>> tokens.  For that, your T[] must be lightweight, it must reference a 
>>>>> bigger piece of data, and it must guarantee not to write anything into 
>>>>> memory outside its boundaries.
>>>>>
>>>>> The Array is for appending.  It must always own its memory.  Therefore 
>>>>> you should be able to pass it around by reference, so Array is a 
>>>>> *class* and cannot be nearly as lightweight as T[].
>>>>>
>>>>> You see, many of their properties are orthogonal.  If you drop one, you 
>>>>> lose flexibility.
>>>>>
>>>>>> Besides, Array!(T) is not a good name for build-in type.
>>>>> Names are placeholders here, not an actual proposal.
>>>> What's wrong with making Array a library type?
>>> Well, I'd like
>>>   new Object[15];
>>> to be immediately appendable and therefore a syntactic sugar for new 
>>> Array!(Object)(15);
>> I have a nagging impression the syntax Array!(Object) strikes you as hard 
>> on the hand and the eyes...
>>
>> Anyhow the syntax new Object[15] is idiotic because Object[15] is a type 
>> in itself. The syntax makes it next to impossible to actually generate a 
>> fixed-sized array dynamically.
>>
>> In fact here's a challenge for you. Please generate a pointer to an 
>> Object[15] using new.
> 
> struct StaticArray(T, int x)
> {
>    T[x] arr;
> }
> 
> Object[15] * x = &((new StaticArray!(Object, 15)).arr);
> 
> lovely, no ;)  I'd probably make a static function in the template to do it, 
> if it was really important to do that...
> 
> There may be a way to do it nicer with a template alias, but I'm not sure it 
> will work.

auto a = (new Object[5][1]).ptr;

The new operator is the plague.


Andrei