🚀 go-pugleaf

Adam Nash (adamnash@cs.stanford.edu) wrote:
: OK Problem Scenario:

: There is a templatized data structure that is based on type DATA.  This
: data structure features a method that depends on a method in type DATA. 
: Thus, for semantic reasons, the template assumes that DATA is a pointer
: type.
:...
: The problem occurs on the second line.  data is of type DATA, so you
: really want to allocate a new (*DATA).  IE, if DATA is a CBar *, then data
: is a CBar *,
: so we want it to say: data = new CBar;

: How can I do this, only knowing the pointer type?
: IE, is there a version of new that can take the pointer type, rather than
: the actual type?  RTTI is fair game.

How about:
	template <class T>
        T* new_of_ptr(T *  /* ignored */)
	{
	  return new T;
	}

	...
	DATA value = new_of_ptr((DATA)0);
	...

-- 
        Tony Cook - tony@online.tmx.com.au
                    100237.3425@compuserve.com
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