refactor: remove toplevel property access

package.json

@@ -189,7 +189,7 @@
     "benchmark": "2.1.0",
     "benchpress": "2.0.0-beta.1",
     "chai": "4.1.2",
-    "check-side-effects": "0.0.17",
+    "check-side-effects": "0.0.20",
     "color": "3.0.0",
     "colors": "1.1.2",
     "commitizen": "2.9.6",
@@ -241,6 +241,7 @@
     "tsconfig-paths": "3.2.0",
     "tslint": "5.9.1",
     "tslint-etc": "1.2.6",
+    "tslint-no-toplevel-property-access": "0.0.2",
     "tslint-no-unused-expression-chai": "0.0.3",
     "typescript": "^3.0.1",
     "validate-commit-msg": "2.14.0",

src/internal/observable/ConnectableObservable.ts

@@ -55,19 +55,20 @@ export class ConnectableObservable<T> extends Observable<T> {
   }
 }
 
-const connectableProto = <any>ConnectableObservable.prototype;
-
-export const connectableObservableDescriptor: PropertyDescriptorMap = {
-  operator: { value: null },
-  _refCount: { value: 0, writable: true },
-  _subject: { value: null, writable: true },
-  _connection: { value: null, writable: true },
-  _subscribe: { value: connectableProto._subscribe },
-  _isComplete: { value: connectableProto._isComplete, writable: true },
-  getSubject: { value: connectableProto.getSubject },
-  connect: { value: connectableProto.connect },
-  refCount: { value: connectableProto.refCount }
-};
+export const connectableObservableDescriptor: PropertyDescriptorMap = (() => {
+  const connectableProto = <any>ConnectableObservable.prototype;
+  return {
+    operator: { value: null as null },
+    _refCount: { value: 0, writable: true },
+    _subject: { value: null as null, writable: true },
+    _connection: { value: null as null, writable: true },
+    _subscribe: { value: connectableProto._subscribe },
+    _isComplete: { value: connectableProto._isComplete, writable: true },
+    getSubject: { value: connectableProto.getSubject },
+    connect: { value: connectableProto.connect },
+    refCount: { value: connectableProto.refCount }
+  };
+})();
 
 class ConnectableSubscriber<T> extends SubjectSubscriber<T> {
   constructor(destination: Subject<T>,

src/internal/observable/dom/AjaxObservable.ts

@@ -486,19 +486,21 @@ export interface AjaxErrorCtor {
   new(message: string, xhr: XMLHttpRequest, request: AjaxRequest): AjaxError;
 }
 
-function AjaxErrorImpl(this: any, message: string, xhr: XMLHttpRequest, request: AjaxRequest): AjaxError {
-  Error.call(this);
-  this.message = message;
-  this.name = 'AjaxError';
-  this.xhr = xhr;
-  this.request = request;
-  this.status = xhr.status;
-  this.responseType = xhr.responseType || request.responseType;
-  this.response = parseXhrResponse(this.responseType, xhr);
-  return this;
-}
-
-AjaxErrorImpl.prototype = Object.create(Error.prototype);
+const AjaxErrorImpl = (() => {
+  function AjaxErrorImpl(this: any, message: string, xhr: XMLHttpRequest, request: AjaxRequest): AjaxError {
+    Error.call(this);
+    this.message = message;
+    this.name = 'AjaxError';
+    this.xhr = xhr;
+    this.request = request;
+    this.status = xhr.status;
+    this.responseType = xhr.responseType || request.responseType;
+    this.response = parseXhrResponse(this.responseType, xhr);
+    return this;
+  }
+  AjaxErrorImpl.prototype = Object.create(Error.prototype);
+  return AjaxErrorImpl;
+})();
 
 export const AjaxError: AjaxErrorCtor = AjaxErrorImpl as any;
 

src/internal/observable/dom/ajax.ts

@@ -79,4 +79,4 @@ import {  AjaxObservable, AjaxCreationMethod  } from './AjaxObservable';
  *
  * ```
  */
-export const ajax: AjaxCreationMethod = AjaxObservable.create;
+export const ajax: AjaxCreationMethod = (() => AjaxObservable.create)();

src/internal/observable/fromEvent.ts

@@ -4,7 +4,7 @@ import { isFunction } from '../util/isFunction';
 import { Subscriber } from '../Subscriber';
 import { map } from '../operators/map';
 
-const toString: Function = Object.prototype.toString;
+const toString: Function = (() => Object.prototype.toString)();
 
 export interface NodeStyleEventEmitter {
   addListener: (eventName: string | symbol, handler: NodeEventHandler) => this;

src/internal/symbol/observable.ts

@@ -8,4 +8,4 @@ declare global {
 }
 
 /** Symbol.observable or a string "@@observable". Used for interop */
-export const observable = typeof Symbol === 'function' && Symbol.observable || '@@observable';
+export const observable = (() => typeof Symbol === 'function' && Symbol.observable || '@@observable')();

src/internal/symbol/rxSubscriber.ts

@@ -1,8 +1,8 @@
 /** @deprecated do not use, this is no longer checked by RxJS internals */
-export const rxSubscriber =
+export const rxSubscriber = (() =>
   typeof Symbol === 'function'
     ? Symbol('rxSubscriber')
-    : '@@rxSubscriber_' + Math.random();
+    : '@@rxSubscriber_' + Math.random())();
 
 /**
  * @deprecated use rxSubscriber instead

src/internal/util/ArgumentOutOfRangeError.ts

@@ -5,14 +5,18 @@ export interface ArgumentOutOfRangeErrorCtor {
   new(): ArgumentOutOfRangeError;
 }
 
-function ArgumentOutOfRangeErrorImpl(this: any) {
-  Error.call(this);
-  this.message = 'argument out of range';
-  this.name = 'ArgumentOutOfRangeError';
-  return this;
-}
+const ArgumentOutOfRangeErrorImpl = (() => {
+  function ArgumentOutOfRangeErrorImpl(this: any) {
+    Error.call(this);
+    this.message = 'argument out of range';
+    this.name = 'ArgumentOutOfRangeError';
+    return this;
+  }
+
+  ArgumentOutOfRangeErrorImpl.prototype = Object.create(Error.prototype);
 
-ArgumentOutOfRangeErrorImpl.prototype = Object.create(Error.prototype);
+  return ArgumentOutOfRangeErrorImpl;
+})();
 
 /**
  * An error thrown when an element was queried at a certain index of an

src/internal/util/EmptyError.ts

@@ -5,14 +5,18 @@ export interface EmptyErrorCtor {
   new(): EmptyError;
 }
 
-function EmptyErrorImpl(this: any) {
-  Error.call(this);
-  this.message = 'no elements in sequence';
-  this.name = 'EmptyError';
-  return this;
-}
+const EmptyErrorImpl = (() => {
+  function EmptyErrorImpl(this: any) {
+    Error.call(this);
+    this.message = 'no elements in sequence';
+    this.name = 'EmptyError';
+    return this;
+  }
+
+  EmptyErrorImpl.prototype = Object.create(Error.prototype);
 
-EmptyErrorImpl.prototype = Object.create(Error.prototype);
+  return EmptyErrorImpl;
+})();
 
 /**
  * An error thrown when an Observable or a sequence was queried but has no