Hiding class pointers -- was it a good idea?

[Daniel919]

Matthias Walter schrieb:
> Bill Baxter Wrote:
> 
>> eao197 wrote:
>>> On Thu, 16 Aug 2007 01:35:17 +0400, Walter Bright 
>>> <newshound1 at digitalmars.com> wrote:
>>>
>>>> 3) Value types just don't work for polymorphic behavior. They must be 
>>>> by reference. There's no way in C++ to ensure that your class 
>>>> instances are used properly by reference only (hence (2)). In fact, in 
>>>> C++, it's *extra work* to use them properly.
>>> But from another side all types in C++ (internal or user defined) is a 
>>> first class citizens. It is especially important in generic programming, 
>>> where I can write:
>>>
>>> template< class T >
>>> class ValueHolder {
>>>   T * m_value
>>> public :
>>>   ValueHolder() : m_value( new T() ) {}
>>>   ...
>>> };
>>>
>>> and this code will work as with int, as with std::string, as with 
>>> ValueHolder<SomeAnotherType>.
>> I hear you.  Fortunately it's pretty trivial to throw some 
>> static-if-is-zzle at the problem in D.  May not be so pretty, but it's 
>> straightforward at least.

class ValueHolder(T) {
private:
	T m_value;

public:
   this() {
	static if(is(T == class))
		m_value = new T;
	else
		m_value = *(new T);
	}
}

> What about letting "new int" do nothing and new int (2) be a simple "2"?
> Then, T foo = new T(); and T foo = new T(2); would work, too.

I like this idea. Let me give an example:

struct stPoint { int x,y; }
class  clPoint { int x,y; }

stPoint p = new stPoint;
clPoint p = new clPoint;

The former is not working, atm it has to be:
stPoint p = *(new stPoint);


new Something
Intuitively I would expect it to return an instance of type Something.
If I wanted a ptr, I would write:
&(new Something)
and get a: Something*

This looks consistent to me.

Any situation where it could cause trouble ?