The withTogglePointFactory accepts a logError argument, for logging errors when an ErrorBoundary catches errors within variant code.
This is currently mandatory, which may not be suitable for all consumers.
Also, this side-effect could be aligned with the "plugin" concept, currently only used for a "code selection" hook, but perhaps would be more consistent if a onError hook was added, to which plugins could listen for logging purposes, or otherwise.
Relates to #30