Template literals | Template strings

Template literals in ES6 (EcmaScript) allows us to embed expressions to our string literals. We can use multi-line strings and string interpolation features with them.

Template literals are enclosed by the back-tick (` `) instead of double or single quotes.

var message = `single line string`;

// single line string

We can include place holders for string substitution using ${ } syntax

var expression = "place holder"; // string substitution
console.log(`this is a text with ${expression} in a line`);

// this is a text with place holder in a line

We can directly use expression interpolation to embed inline math

var a = 5;
var b = 5;

console.log(`the addition of a+b = ${a+b}`);
// the addition of a+b = 10

We can also call functions and use member functions in strings

function sample() { return "text from sample method"; }

console.log(`yes! ${sample()} and i am in uppercase`.toUpperCase());


The above code retrieves data from sample() method and converts it to uppercase in run-time.

Multiline Strings

We can achieve multi line strings, previously we used to insert new line character in our string

console.log(`First line
Second line`);
// First line 
// Second line

Raw strings

The special raw property, available on the first function argument of tagged template literals, allows you to access the raw strings as they were entered.

String.raw`Hi \n ${2+3}!`;
// "Hi \n 5!"

Tagged template literals

A more advanced form of template literals are tagged template literals. With them we able to modify the output of template literals using a function. The first argument contains an array of string literals. The second, and each argument after the first one, are the values of the processed substitution expressions. We can use any name to our function.

var a = 1;
var b = 2;

function tag(strings, ...values) {
 console.log(strings[0]); // "One "
 console.log(strings[1]); // " Two"
 console.log(strings[2]); // " Three"
 console.log(values[0]); // 1
 console.log(values[1]); // 2

tag`One ${ a } Two ${ b } Three`;

// One 
// Two 
// Three
// 1
// 2

Happy exploring EcmaScript 🙂

Angular 9 Tutorial: Project Structure

In the previous post, we have discussed how to create hello world application in angular. Using Angular CLI, we have generated basic files needed to run a hello world application.

Now, let’s have a quick look at the files and folders in our new Angular project.

The generated projects have the following files and folders structure

The top level of the workspace contains workspace-wide configuration files, configuration files for the root-level application, and subfolders for the root-level application source and test files.

.editorconfigConfiguration for code editors. See EditorConfig.
.gitignoreSpecifies intentionally untracked files that Git should ignore.
README.mdIntroductory documentation for the root app.
angular.jsonCLI configuration defaults for all projects in the workspace, including configuration options for build, serve, and test tools that the CLI uses, such as TSLintKarma, and Protractor. For details, see Angular Workspace Configuration.
package.jsonConfigures npm package dependencies that are available to all projects in the workspace. See npm documentation for the specific format and contents of this file.
package-lock.jsonProvides version information for all packages installed into node_modules by the npm client. See npm documentation for details. If you use the yarn client, this file will be yarn.lock instead.
src/Source files for the root-level application project.
node_modules/Provides npm packages to the entire workspace. Workspace-wide node_modules dependencies are visible to all projects.
tsconfig.jsonDefault TypeScript configuration for projects in the workspace.
tslint.jsonDefault TSLint configuration for projects in the workspace.

Application source files

Files at the top level of src/ support testing and running your application. Subfolders contain the application source and application-specific configuration.

app/Contains the component files in which your application logic and data are defined. See details below.
assets/Contains image and other asset files to be copied as-is when you build your application.
environments/Contains build configuration options for particular target environments. By default there is an unnamed standard development environment and a production (“prod”) environment. You can define additional target environment configurations.
favicon.icoAn icon to use for this application in the bookmark bar.
index.htmlThe main HTML page that is served when someone visits your site. The CLI automatically adds all JavaScript and CSS files when building your app, so you typically don’t need to add any <script> or<link> tags here manually.
main.tsThe main entry point for your application. Compiles the application with the JIT compiler and bootstraps the application’s root module (AppModule) to run in the browser. You can also use the AOT compiler without changing any code by appending the --aot flag to the CLI build and serve commands.
polyfills.tsProvides polyfill scripts for browser support.
styles.sassLists CSS files that supply styles for a project. The extension reflects the style preprocessor you have configured for the project.
test.tsThe main entry point for your unit tests, with some Angular-specific configuration. You don’t typically need to edit this file.

Inside the src/ folder, the app/ folder contains your project’s logic and data. Angular components, templates, and styles go here.

app/app.component.tsDefines the logic for the app’s root component, named AppComponent. The view associated with this root component becomes the root of the view hierarchy as you add components and services to your application.
app/app.component.htmlDefines the HTML template associated with the root AppComponent.
app/app.component.cssDefines the base CSS stylesheet for the root AppComponent.
app/app.component.spec.tsDefines a unit test for the root AppComponent.
app/app.module.tsDefines the root module, named AppModule, that tells Angular how to assemble the application. Initially declares only the AppComponent. As you add more components to the app, they must be declared here.

Application configuration files

The application-specific configuration files for the root application reside at the workspace root level. For a multi-project workspace, project-specific configuration files are in the project root, under projects/project-name/.

Project-specific TypeScript configuration files inherit from the workspace-wide tsconfig.json, and project-specific TSLint configuration files inherit from the workspace-wide tslint.json.

browserslistConfigures sharing of target browsers and Node.js versions among various front-end tools. See Browserslist on GitHub for more information.
karma.conf.jsApplication-specific Karma configuration.
tsconfig.app.jsonApplication-specific TypeScript configuration, including TypeScript and Angular template compiler options. See TypeScript Configuration and Angular Compiler Options.
tsconfig.spec.jsonTypeScript configuration for the application tests. See TypeScript Configuration.
tslint.jsonApplication-specific TSLint configuration.



Course Main page

Angular 9 Tutorial for Beginners: Action Plan