Package delitmus lifts the c4f delitmusifier into a backend.

Package herdstyle contains backends that c4f in a similar way to the Herd memory simulator.

ErrNil occurs when the backend we try to resolve is nil.

ErrUnknownStyle occurs when we ask the resolver for a backend style of which it isn't aware.

Resolve is a pre-populated backend resolver.

Resolver maps backend styles to classes, and implements a resolver accordingly.