Function EvalStateObserver

interpreter/interpreter.go:94–107

EvalStateObserver provides an observer which records the value associated with the given expression id. EvalState must be provided to the observer.

(opts ...evalStateOption)

// EvalStateObserver provides an observer which records the value associated with the given expression id.
// EvalState must be provided to the observer.
func EvalStateObserver(opts ...evalStateOption) PlannerOption {
	et := &evalStateFactory{factory: NewEvalState}
	for _, o := range opts {
		et = o(et)
	}
	return func(p *planner) (*planner, error) {
		if et.factory == nil {
			return nil, errors.New("eval state factory not configured")
		}
		p.observers = append(p.observers, et)
		p.decorators = append(p.decorators, decObserveEval(et.Observe))
		return p, nil
	}
}

// activationWrapper identifies an object carrying local variables which should not be exposed to the user
// Activations used for such purposes can be unwrapped to return the activation which omits local state.