Should I compare pointers with is of == ?

[Max Samukha]

On Wed, 14 Oct 2009 14:20:24 -0400, Justin Johansson <no at spam.com>
wrote:

>#ponce Wrote:
>
>> It's a bit unclear to me. 
>> 
>> I know I must compare references with is but pointers ?
>
>Thanks for asking this question ponce; I've been getting into the habit of using 'is' for both pointers
>and classes, so in similar vein to ponce's question, I'd like to ask if the following (where foo is
>eother a pointer of class ref) is being overly pendantic in the case of null if tests:
>
>if (foo !is null) {
>  // can do something with foo
>}
>
>as opposed to the shorter form, but possibly incorrect or less safe
>
>if (foo) {
>  // can do somthing with foo
>}
>
>I think I would prefer the shorter form if its 100% good.

If you compare pointers or class references, it is 100% good to use
the shorter form. It is only 87% good if you compare arrays because
the shorter form means "if (arr.ptr)". So, if you are in the camp of
those who do not make a distinction between empty and null arrays you
should always use "if (arr.length)".

>
>Thanks all.