TypeScript and JavaScript are currently two popular scripting languages in project development. We are already familiar with TypeScript as a superset of JavaScript, but what is the difference between TypeScript and JavaScript? When choosing a development language, how should one choose?
This article will compare the two languages in depth, discuss the associations and differences between the two languages, and outline the advantages of the two languages.
1. Overview of JavaScript and TypeScript
1.1 JavaScript
JavaScript is a lightweight explanatory scripting language that can be embedded in HTML pages and executed on the browser side. It can implement rich interactive functions on the browser side and bring users a smooth and diverse user experience.
JavaScript is based on object and event-driven, no specific language environment is required, and it can be run on only supported browsers.
JavaScript language has the following characteristics
- JavaScript is a scripting language that does not need to be compiled, as long as it is embedded in the HTML code, it can be loaded and interpreted line by line by the browser.
- JavaScript is an object-based language that can create objects while using existing objects. But Javascript does not support the inheritance and overloading functions of other object-oriented languages.
- The syntax of JavaScript is simple, and the variables used are weakly typed.
- The JavaScript language is relatively safe and is only executed on the browser side without accessing local hard disk data.
- The JavaScript language is dynamic. JavaScript is event-driven and only responds to the user’s actions.
- JavaScript only depends on the browser and has nothing to do with operating system factors. Therefore JavaScript is a cross-platform language.
- JavaScript has good compatibility and can be used with other technologies (such as XML, REST API, etc.).
1.2 TypeScript
TypeScript is an object-oriented programming language developed and maintained by Microsoft. It is a superset of JavaScript, contains all the elements of JavaScript, can load JavaScript code to run, and extends the syntax of JavaScript.
TypeScript has the following characteristics
- TypeScript is an open source language launched by Microsoft and uses the Apache license agreement.
- TypeScript adds static types, classes, modules, interfaces, and type annotations.
- TypeScript can be used to develop large applications.
- TypeScript is easy to learn and understand.
2. Differences between JavaScript and TypeScript
TypeScript can use all the codes and coding concepts in JavaScript. TypeScript was created to make JavaScript development easier. For example, TypeScript uses concepts such as types and interfaces to describe the data being used, which enables developers to quickly detect errors and debug applications.
- TypeScript extends the JavaScript object model from the core language aspect and the modeling aspect of the class concept.
- JavaScript code can work with TypeScript without any modification, and a compiler can be used to convert TypeScript code into JavaScript.
- TypeScript provides static type checking at compile time through type annotations.
- The data in TypeScript requires a clear type, but JavaScript does not require it.
- TypeScript provides default parameter values for functions.
- TypeScript introduces the concept of “classes” not found in JavaScript.
- TypeScript introduces the concept of modules, which can encapsulate declarations, data, functions, and classes in modules.
3. Advantages of TypeScript
The following shows the obvious advantages of TypeScript over JavaScript
3.1 Static input
Static typing is a feature that can detect errors when developers write scripts. Finding and fixing errors is an urgent need for development teams today. With this feature, it will allow developers to write more robust code and maintain it in order to make the code quality better and clearer.
3.2 Large-scale development project
Sometimes in order to improve the development project, small incremental changes to the code base are required. These small changes may have serious and unexpected consequences, so it is necessary to undo these changes. Using TypeScript tools to refactor is easier and faster.
3.3 Better collaboration
When a large-scale project is launched, there will be many developers, and the chances of garbled and error will also increase. Type safety is a feature that detects errors during coding, not when compiling the project. This creates a more efficient coding and debugging process for the development team.
3.4 Stronger productivity
Factors such as clean ECMAScript 6 code, auto-completion and dynamic input help improve the efficiency of developers. These features also help the compiler to create optimized code.
4. Advantages of JavaScript
Compared to TypeScript, JavaScript also has some obvious advantages
4.1 Popularity
The JavaScript developer community is still huge and active, and a large number of mature development projects and available resources can be easily found in the community.
4.2 learning curve
Due to the earlier and more mature development of the JavaScript language, there are still a large number of developers who insist on using their familiar scripting language JavaScript instead of learning TypeScript.
4.3 Native browser support
TypeScript code needs to be compiled (to output JavaScript code), which is an additional step when TypeScript code is executed.
4.4 No comments needed
In order to take full advantage of TypeScript features, developers need to continuously comment their code, which may reduce the efficiency of the project.
4.5 flexibility
Some developers prefer the flexibility of JavaScript.
5. How to choose
TypeScript is becoming a powerful tool for developing large coding projects. Because the structure of its object-oriented programming language keeps the code clean, consistent and easy to debug. Therefore, when dealing with large-scale development projects, it is more appropriate to use TypeScript. If you have a relatively small coding project, it seems unnecessary to use TypeScript, just use flexible JavaScript.