Method collectionObserver

src/binding-engine.js:42–61

(collection)

  }

  collectionObserver(collection) {
    return {
      subscribe: callback => {
        let observer;
        if (collection instanceof Array) {
          observer = this.observerLocator.getArrayObserver(collection);
        } else if (collection instanceof Map) {
          observer = this.observerLocator.getMapObserver(collection);
        } else if (collection instanceof Set) {
          observer = this.observerLocator.getSetObserver(collection);
        }  else {
          throw new Error('collection must be an instance of Array, Map or Set.');
        }
        observer.subscribe(callback);
        return {
          dispose: () => observer.unsubscribe(callback)
        };
      }
    };
  }

  expressionObserver(bindingContext, expression) {
    let scope = { bindingContext, overrideContext: createOverrideContext(bindingContext) };