Why is array truth tied to .ptr?

[Bill Baxter]

Derek Parnell wrote:
> On Mon, 10 Dec 2007 10:52:00 +0900, Bill Baxter wrote:
>  
>> In a nutshell,
>>     if(array)
>> is synonymous with
>>     if(array.ptr)
>> but I believe it makes much more sense for it to be synonymous with
>>     if(array.length)
>> since that's the thing you want to be checking 99.9% of the time.
> 
> I'm guessing that this behaviour is due to the commonly used idiom for all
> reference types, namely that the test is against the 'pointer' value rather
> than any other aspect of the item being referenced.
> 
>    class Foo {};
> 
>    Foo f = new Foo();
>    Foo g;
>    if (f) ...
>    if (g) ...
> 
>    long *lp;
>    if (lp) ...
> 
> Personally, I regard this as a shorthand option that should be avoided on
> legibility grounds. 
> 
> I prefer the more explicit versions ...
> 
>    if (array.ptr !is null)
>    if (array.length != 0) 
>    if (f !is null)
>    if (lp !is null)
> 
> only because this is harder to misunderstand.

I'm just too lazy to type that much. :-)

--bb