Get Programming with JavaScript Next

Lesson 8. Capstone: Building a domain-specific language

In this project, you will

• Learn what a domain-specific language (DSL) is
• Create a simple DSL for handling user input from an HTML formatter
• Create a simple DSL for repeating or looping templates around an array

Before you build a DSL, let’s first define what one is. A domain-specific language uses a programming language’s features and syntax in a clever way to make solving a particular task appear as if it has first-class support by the programming language itself. For example, a common type of DSL seen in JavaScript is used by unit test libraries:

describe('push', function() {
  it('should add new values to the end of an array', function() {
    // perform test
  });
});

This is a DSL because ...