🚀 go-pugleaf

In article <1d1oirINN3vu@agate.berkeley.edu> jbuck@forney.berkeley.edu (Joe Buck) writes:
| In article <1992Nov1.201547.4661@cs.brown.edu> sdm@cs.brown.edu (Scott Meyers) writes:
| >Hence, given that this is legal,
| >
| >    T *p;
| >    void *q = p;
| >
| >is there a good reason why this isn't?
| >
| >    void f(T*);
| >    void (*pf)(void*) = f;
| 
| Certainly.  Consider the line that would be legal next:
| 
| T2* p;	// class T2 has no relation to class T
| pf(p);
| 
| Now we have passed a pointer to T2 to a function that thinks it is getting
| a pointer to T, and we have broken the type system.

Boy, either I'm really dense or what we have here is a failure to
communicate.  Clearly (I hope), if pf wants to do anything with its
argument, it has to know what the real type is, i.e., it's going to have to
do an explicit cast from void* to whatever the type really is.  Obviously
this gives rise to the spector of type errors, but so does any use of void*
pointers.  So my question is really whether there are any possibilities of
type errors other than those inherent in the use of void* pointers.

Scott

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