(re:
RigidArray) In some early drafts, that was indeed the working name for this type.
(Fun anecdote: the moment that turned our draft RigidArray type into a bona fide vector was particularly noteworthy. In the early days, we planned our precursor type to be unconditionally noncopyable — until one particularly memorable & productive engineering discussion, where we decided that it needs to become conditionally copyable (despite the immense extra complexity this adds to its implementation).
That very same day, two separate groups of people independently realized that copyability has now turned this type into a true vector, and that Vector is the obviously right name for this construct. This made for a comical scene when members of the two groups met up later in the day, fully expecting that they’d need to convince the other.
This was the only time I ever experienced such a naming miracle; I do not expect it to ever see it happen again. It has left me with a rock solid conviction that Vector is the right name for this shape — I feel it deep in my bones, and it would take quite some effort to convince me otherwise.
In contrast, the name Span was a very difficult birth — it took months of diligent effort to convince people about it. The type’s mediocre (at best) working titles have even made it into some formal pitch documents!)