More detail on 'missing getter' error.
Use exportExpressions instead of ng-model.

Lets angular generate the static getter expression for bits. Both approaches are to avoid the error 'Missing getter: (o) => o.bits'.
Fewer components.
Add some tests for hex_parser.dart.
Simpler: feed angular integers instead of references.

Ditch Byte and list mutation. Pass angular two integers. Use those to find the bit: 1 or 0.