CPP13 — fixed-length _var assignment from pointer

the new mapping for _var types for fixed-length underlying types shows:

T_var &operator=(T *t) {
if (t != m_ptr)

return *this;
}

This guards against self assignment when a pointer is assigned to the _var.

I don't think this is right:

• Assigning a pointer to a _var that already owns what the pointer
  points at is almost certainly an error:

MyStruct * p = ...;
MyStruct_var v = p; // OK

// ...

v = p; // Almost certainly an error

• We don't do the same thing elsewhere. On page 1-13:

A_var &operator=(const A_var& a)

This is inconsistent: assignment of a _ptr to a _var reference
is not safe against self assignment, so assignment of a pointer
to the _var for a fixed-length type shouldn't be either.

Note that the other assignment operators are just fine – I'm only objecting
to testing for self-assignment for operator= with a pointer as the RHS.
(A nice compiler could even insert an assertions if a _var is assigned the
same thing that it already points at.)