Deep Analysis and Solutions for Observable.map Missing Issue in Angular 2 beta.17 Upgrade

Problem Background and Error Analysis

During the upgrade from Angular 2 beta.16 to beta.17, many developers encountered type compilation errors, primarily manifesting as <span class="code">Property 'map' does not exist on type 'Observable<Response>'</span>. The root cause lies in beta.17's introduction of rxjs 5.0.0-beta.6, which significantly changed operator import mechanisms.

The error messages mentioning <span class="code">Ambient modules cannot be nested in other modules or namespaces</span> and <span class="code">Ambient module declaration cannot specify a relative module name</span> indicate that the TypeScript compiler encountered module declaration conflicts when processing rxjs type definition files. This is typically caused by TypeScript configuration or build tool version incompatibility.

Core Solution

Based on the best answer analysis, resolving this issue requires a multi-layered approach:

First, ensure proper import of rxjs operators. The appBoot.ts file must include:
import 'rxjs/add/operator/map';
import 'rxjs/add/operator/toPromise';

However, this alone is insufficient. A crucial step is updating build tools. Upgrading the gulp-typescript plugin from version 2.12.0 to 2.13.0 resolves most compilation issues. The newer version better handles nested type definition files in rxjs 5.

For users upgrading to Angular 2.0.0-rc.1, additional type reference path adjustments are needed:
<reference path="./../typings/browser/ambient/es6-shim/index.d.ts"/>

The es6-shim type definition file provides essential ES6 feature support, ensuring modern JavaScript features like Observable are correctly recognized by TypeScript. These type definitions can be installed via the typings tool:
typings install dt~es6-shim --global --save

rxjs Version Differences and Operator Import Methods

In rxjs 5.5 and later versions, operator import methods evolved further. As noted in supplementary answers, pipe operators should be used instead:
this.myObservable().pipe(map(data => {}))

The corresponding import statement becomes:
import { map } from 'rxjs/operators';

This change reflects rxjs's shift toward a more functional programming style, enabling operator composition and reuse through pipe operators. While Angular 2 beta.17 uses rxjs 5.0.0-beta.6, understanding this evolution is valuable for future upgrades.

Configuration Optimization Recommendations

To ensure long-term project stability, consider the following configuration optimizations:

1. Unify TypeScript configuration to ensure module resolution strategies in <span class="code">tsconfig.json</span> are compatible with the rxjs version
2. Regularly update build toolchains, especially TypeScript compilation-related plugins
3. Use typings to manage all type definition dependencies, avoiding manual modifications to <span class="code">.d.ts</span> files
4. Consult official changelogs before upgrading Angular versions to understand requirements for rxjs and other dependencies

By systematically addressing type definitions, build tools, and import mechanisms, developers can successfully complete the Angular 2 beta.17 upgrade and establish a solid foundation for future version migrations.