Every new change

node_modules/rxjs/src/internal/BehaviorSubject.ts

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+import { Subject } from './Subject';
+import { Subscriber } from './Subscriber';
+import { Subscription } from './Subscription';
+import { SubscriptionLike } from './types';
+import { ObjectUnsubscribedError } from './util/ObjectUnsubscribedError';
+
+/**
+ * A variant of Subject that requires an initial value and emits its current
+ * value whenever it is subscribed to.
+ *
+ * @class BehaviorSubject<T>
+ */
+export class BehaviorSubject<T> extends Subject<T> {
+
+  constructor(private _value: T) {
+    super();
+  }
+
+  get value(): T {
+    return this.getValue();
+  }
+
+  /** @deprecated This is an internal implementation detail, do not use. */
+  _subscribe(subscriber: Subscriber<T>): Subscription {
+    const subscription = super._subscribe(subscriber);
+    if (subscription && !(<SubscriptionLike>subscription).closed) {
+      subscriber.next(this._value);
+    }
+    return subscription;
+  }
+
+  getValue(): T {
+    if (this.hasError) {
+      throw this.thrownError;
+    } else if (this.closed) {
+      throw new ObjectUnsubscribedError();
+    } else {
+      return this._value;
+    }
+  }
+
+  next(value: T): void {
+    super.next(this._value = value);
+  }
+}