Re: [boost] null

29 Jul 2005

      Eric Niebler wrote:
...
Jason Hise wrote:
...
Martin Wille wrote:
...
Jason Hise wrote:
...
undef NULL
#define NULL (::boost::null)
What existing code will it break?
struct foo {};
typedef void (foo::*memfunptr)();
memfunptr p = NULL;
Bad example. This is OK, somewhat surprisingly (to me, at least). But 
consider:

struct foo { foo(void*) {} };
void bar(foo f) {}
void baz() {
   bar(NULL);
}

Works with NULL as 0, fails with NULL as null because it needs two 
user-defined conversions.
...
Redefining NULL is a career-limiting move. Don't do it.
This is still correct, though.

-- 
Eric Niebler
Boost Consulting
www.boost-consulting.com