.idup flawed?

[Xinok]

.idup creates an invariant copy of an array. According to this page:
http://digitalmars.com/d/const.html

"One is that constant data really is constant. It never changes. It's 
different enough that it needs a different name. In D, this kind of 
constant is called an invariant."


So if you have an invariant array, you expect that it's data will never 
change.

This is not always the case if you have an array of classes. Classes are 
pointers, and when you use the .idup property, it only creates invariant 
copies of the pointers, and not the objects themselves. This means that 
the objects are still mutable and the data can change, which is not the 
intended behavior of invariant.