User defined attributes use

[ilya-stromberg]

On Monday, 16 September 2013 at 15:12:05 UTC, Maxim Fomin wrote:
> On Monday, 16 September 2013 at 10:29:12 UTC, matovitch wrote:
>> All your examples are great, thank you ! Is there a way to 
>> omit validate such that the compiler would call it implicitly ?
>>
>> For example :
>>
>> class C {
>>  ...
>> }
>>
>> void fun(@nonNull C c) {
>>  ...
>> };
>>
>> C c;
>> fun(c);  //compilation error since C is null
>
> No, this isn't doable with UDAs because what you want requires 
> runtime check. It is doable using other language features.

It's intresting how can I check that pointer is not null at the 
compile time. Can you print a example, please?
I know that we can use contract programming, but it requires 
runtime check.