Previous commit changed DOM fragment representation to use strings
instead of Seal'd quasi-sexprs, and so eliminated any distinction
between textually-identical DOM fragments in the dataspace.
This patch disables the "spawn" buttons for components in the IoT demo
to avoid (mostly harmless) duplication of actor instances.
It also demonstrates use of react{} outside a *lexically*-enclosing
actor{}.
This avoids churn in the dataspace for no-op DOM updates, but at the
cost of losing the identity of multiple pieces of asserted DOM when
they end up being textually identical.
The fix is, generally, to make sure your DOM fragments are different
in some (perhaps invisible when rendered) way. Next commit updates the
IoT demo to avoid duplicate fragments.
Sam Caldwell
Tony Garnock-Jones