🚀 go-pugleaf

In article <45ns7a$cir@panix.com> you write:
>In article <45mor5$fms@jupiter.SJSU.EDU>,
>Cay S. Horstmann <horstman@jupiter.SJSU.EDU> wrote:
>>clamage@Eng.sun.com (Steve Clamage) wrote:
>>
>>>In article 100000@gusak, "Brett W. Denner" <dennerbw@cliffy.lfwc.lockheed.co
m>
>> writes:
>>>>Is there a way to identify whether a data type in a template function is a
>>>>class or a built-in type?  For example,
>
>How about using template specialization?
>	template<class T> bool builtin() { return false; }
>	template<class T> bool builtin<char>() { return true; }

Why not use RTTI ? typeid() will tell you the info you need...

from G++ 2.7.0 typeinfo.h:

// RTTI support: typeinfo.h
// Written by Kung Hsu based upon the specification in the 20 September 1994
// C++ working paper, ANSI document X3J16/94-0158.

class type_info {
private:
  // assigning type_info is not supported.  made private.
  type_info& operator=(const type_info&);
  type_info(const type_info&);

public:
  enum node_type {
    _RTTI_BUILTIN_TYPE,               // builtin type
    _RTTI_USER_TYPE,                  // user defined type
    _RTTI_CLASS_TYPE,                 // class type
    _RTTI_POINTER_TYPE,               // pointer type
    _RTTI_ATTR_TYPE,                  // attribute type for const and volatile
    _RTTI_FUNC_TYPE,                  // function type
    _RTTI_PTMF_TYPE,                  // pointer to member function type
    _RTTI_PTMD_TYPE                   // pointer to member data type
    };

  // return node type of the object
  virtual node_type __rtti_get_node_type() const {}
<remainder deleted>

so to determine the type of object x...

if(typeid(x).__rtti_get_node_type() == _RTTI_BUILTIN_TYPE)
	cout << "x is a builtin type" << endl;
else if if(typeid(x).__rtti_get_node_type() == _RTTI_CLASS_TYPE)
	cout << "x is a class type" << endl;
etc.


Ethan
-- 
Ethan Henry                                                  ethan@learnix.ca
Instructor, Learnix Inc.                          Visit http://www.learnix.ca
 "Don't try to outweird me - I get weirder stuff than you free in my
   breakfast cereal." -Z. Beeblebrox, quoted in the Design & Evolution of C++
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