[vtk-developers] hast table in VTK

[Brad King]

Moreland, Kenneth wrote:
> The pointer value is not always a valid value to hash on.  Sometimes
> objects that have different pointers can be considered equal.

In that case the object is not stored in the map and really is a key to 
something else, even if it is an object considered equal.

If the pointer value is not the key then I don't think a single hash key 
virtual function will work either.  The key to use for the object could 
change depending on the application of the hash table.  Instead I 
suggest that the objects be stored paired with another key on which the 
hash function is defined.

-Brad