how to determine a runtime type faster?

[davidl]

umm , ur way rox either. but i don't know if the cast(derive)instance is  
implemented as good as
(instance.classinfo is derive.classinfo)?

> On Thu, 10 May 2007 16:16:42 +0300, davidl <davidl at 126.com> wrote:
>
>> module funky.super.meaningless.modulename;
>> class base
>> {
>> }
>> class derive:base
>> {
>> }
>> void main()
>> {
>>      derive instance= new derive;
>>      base castedinstance=instance;
>>      // notice the following would result a super long string  
>> comparision ,
>> which is not so good.
>>      //
>> `funky.super.meaningless.modulename.derive`==`funky.super.meaningless.modulename.derive`
>>      assert(castedinstance.classinfo.name==derive.classinfo.name);
>>
>> }
>> the idea is castedinstance.classinfo.runtimeid?
>> the runtimeid could generated by the compiler and with some proper  
>> design
>> about object.d , i think
>> the comparision could be faster
>
>  From http://www.digitalmars.com/d/expression.html#CastExpression :
>
>> Any casting of a class reference to a derived class reference is done  
>> with a runtimecheck to make sure it really is a downcast. null is the  
>> result if it isn't. Note: Thisis equivalent to the behavior of the  
>> dynamic_cast operator in C++.
>
> So, for your example you only need:
>
> assert(cast(derive)castedinstance);
>



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