Steve Yegge's rant on The Next Big Language

[Bruno Medeiros]

Thomas Kuehne wrote:
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> Jarrett Billingsley schrieb am 2007-02-13:
>> "BCS" <BCS at pathlink.com> wrote in message 
>> news:eqq7nq$2tut$1 at digitalmars.com...
>>
>>> Half?, more like one or two hard misses and a few more close calls.
>> Well let's see:
> 
> [snip]
> 
>> 15. Static typing and duck typing
>>
>> Yes.  (Unless some duck typing expert wants to correct me, I _think_ D has 
>> it)
> 
> Shouldn't the code below be legal if D supported duck typing?
> #
> # class Cat{
> #    void grow(){}
> # }
> #
> # class Tree{
> #    void grow(){}
> # }
> #
> # void main(){
> #    Tree t = new Cat();
> #    t.grow();
> # }
> 
> Thomas
> 
> 
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Yup, D doesn't actually support duck typing. Not on the object system 
method call at least, since in metaprogramming (compile-time) it has 
something that can be considered duck typing: Using the is-expression to 
test for features:

template func(T) (T foo) {
   static if(is(foo.grow())) {
     foo.grow();
   } else
     ...
}


-- 
Bruno Medeiros - MSc in CS/E student
http://www.prowiki.org/wiki4d/wiki.cgi?BrunoMedeiros#D