Time to look at tsconfig.js which is used to configure TypeScript.
The first block configures the compiler options. The target option is set to es5 so the ECMAScript target version is ECMAScript 5. The module option is set to commonjs so CommonJS is used for module loading. The moduleResolution is set to node so the compiler mimics Node.js’s runtime module resolution. The sourceMap option is set to true so that .map files are generated (.map file are created so debuggers can map compiled code to the source). The emitDecoratorMetadata and experimentalDecorators are set to true to support class metadata using decorators. The removeComments option is true so that comments are available in the compiled .js file. The noImplicitAny and suppressImplicitAnyIndexErrors are set to true so the compiler is more strict and will fail if a type cannot be inferred.
The next block is the exclude section which tells the compiler what directories to ignore. The node_module, typings/main, and typings/main.d.ts are set to be ignored by the compiler.
Another useful excercise in learning what’s going on with an Angular project. Steady progress for the win!