Veto seam for merge. Default: same templatePath, no shadows / adornments on either side, every glob-identity field equal. A future shadow that wants to block (or permit) merging overrides this on its shadow layer.
Veto seam for split. Default: 1 <= n <= getQuantity(), no
shadows on this, no adornments on this. Shadows that know they
split cleanly override to widen.
Current stack size. Always a positive integer.
Witness on the surviving stack after GlobbableApi.merge absorbs
another. No-op terminal so subclasses can
super.onMerged(absorbed).
Witness on the source after GlobbableApi.split produces a new
Stuff. No-op terminal so subclasses can super.onSplit(splitoff).
Set the stack size. Throws on n < 1 or non-integer n. To
"destroy the last one," go through StuffApi.destruct; the
mixin never permits a zero-quantity state.
Public shape added by GlobbableMixin.