Given that Nim has qualifiers like `noinit` (in the memory handling
optimization area, no less), `NoMoveSeq` is another idea family. "move" is
what's used in a few places for address instability. I still kind of like
"unmoved" as the only real possibility of confusion...just isn't there. Data
types are not emotionally moved or persuaded or anything like that. { Ahem. "I
shall be unmoved by further debate!" Just kidding. ;-) } "Inert" is also nice
since AFAICT it's unused much in CS/data structures.
Another problem with "Stable" is that while I know academics & Google &
Facebook use "reference stability" in various hash table docs, this, too has
been pretty heavily corrupted / overloaded. Essentially, "sounding good" (in
sorting algos, too) means it got swept up in what might be called "the
unclarity intrinsic to 'idea marketing' ". E.g., [this
paper](https://arxiv.org/pdf/2109.04548) uses it to mean, I kid you not:
"Stability. If a partial resize has not been triggered in the past O(n)
operations". Talk about semantic dilution!
