Angular Compiler (Ivy)

Angular's Ivy compiler and runtime offer numerous benefits, including faster compilation, better debugging, and improved performance. This guide covers the basics of Ivy and how to leverage its features in your Angular applications.

Enabling Ivy

Ivy is the default rendering engine in Angular since version 9. To ensure Ivy is enabled, check your tsconfig.app.json file:

// tsconfig.app.json
{
  "angularCompilerOptions": {
    "enableIvy": true
  }
}

Using Ivy Features

Ivy introduces several new features and improvements. Here are some key aspects:

Smaller Bundle Sizes

Ivy generates smaller bundle sizes by removing unused code (tree-shaking) and improving template compilation.

Faster Compilation

Ivy speeds up both JIT (Just-in-Time) and AOT (Ahead-of-Time) compilation, making the development process more efficient.

Improved Debugging

Ivy enhances debugging with better error messages and stack traces, making it easier to identify and fix issues.

Lazy Loading Components

With Ivy, you can lazy load components dynamically using the import() syntax:

// some.component.ts
import { Component, NgModuleFactory, Injector } from '@angular/core';
import { loadRemoteModule } from '@angular-architects/module-federation';

@Component({
  selector: 'app-some',
  template: ``
})
export class SomeComponent {
  component: any;

  constructor(private injector: Injector) {}

  async loadComponent() {
    const { LazyComponent } = await import('./lazy/lazy.component');
    const factory = await (LazyComponent as NgModuleFactory).create(this.injector);
    this.component = factory.instance;
  }
}

Incremental DOM

Ivy uses an incremental DOM approach, which improves rendering performance by only updating the parts of the DOM that have changed.

Improved Internationalization (i18n)

Ivy enhances Angular's internationalization capabilities with better support for localization and dynamic loading of translations.

Tree-Shakable Providers

Ivy allows you to create tree-shakable providers, reducing the size of your bundles by only including the services you actually use:

// some.service.ts
import { Injectable, Optional, SkipSelf } from '@angular/core';

@Injectable({
  providedIn: 'root'
})
export class SomeService {
  constructor(@Optional() @SkipSelf() private parentService: SomeService) {
    if (parentService) {
      throw new Error('SomeService is already loaded.');
    }
  }
}

Optimized Change Detection

Ivy optimizes change detection by reducing the number of checks needed to detect changes in the application state.

Key Points

Conclusion

The Angular Ivy compiler and runtime offer significant improvements in performance, debugging, and bundle size. By leveraging Ivy's features, you can enhance the efficiency and maintainability of your Angular applications. Happy coding!