arrays: if(null == [ ])

[Gor Gyolchanyan]

>> P.S. Please don't top-post. It's bad etiquette and makes posts harder to
follow.

It's not me. It's how gmail works.

On Tue, May 15, 2012 at 12:12 AM, Jonathan M Davis <jmdavisProg at gmx.com>wrote:

> On Monday, May 14, 2012 21:16:21 Gor Gyolchanyan wrote:
> > At least we could make an empty string a null array of characters for
> > consistency.
>
> It's completely consintent. If there is memory allocated for the array,
> then
> it's ptr property is non-null, and then the array is non-null per the is
> operator. If there is no memory allocated for the array, then it's ptr
> property is null, and the array is null per the is operator.
>
> It's quite possible to have non-string arrays be non-null with a length of
> 0.
> It just takes more work. e.g.
>
> auto a = new int[](1);
> a.length = 0;
>
> And it would actually be really annoying if "" were treated the same as [],
> because it becomes harder to differentiate between the empty string and a
> null
> string in the few cases where you care. If anything, the fact that []
> doesn't
> allocate is _more_ annoying as far as that goes. But it's more efficient
> that
> way, so that's why [] is null.
>
> > How many times did anyone use the feature of string literals
> > being null-terminated?
>
> It gets used all the time when people call C functions and is a _really_
> good
> reason why making assert("" is null) true would be a _really_ bad idea.
>
> - Jonathan M Davis
>
>
> P.S. Please don't top-post. It's bad etiquette and makes posts harder to
> follow.
>



-- 
Bye,
Gor Gyolchanyan.
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