Or they can add comments and hints, but this does not protect them from misuse. In such a situation, TypeScript comes to the rescue. Let's find out how TypeScript is useful in JavaScript development.
What is TypeScript?
TypeScript (TS) is a programming language for web development based on JavaScript. It makes the code clearer and more robust, adds static typing (variables are bound to specific data types), and can be compiled into JavaScript. TypeScript is used by frontend and backend developers for different complexity-level development.
TypeScript is a strictly typed programming language. It consists of three parts:
- Programming language syntax
- Compiler
- Editor
Code written in TypeScript will not run directly in the browser. This is why TS is not a stand-alone language but rather a language over JS. It requires transpilation when the software converts the code written in TypeScript into JavaScript.
The TypeScript syntax allows the developer to elegantly express the solution to a problem as text in a .ts or .tsx file. It is an evolution of the JavaScript syntax, so any JS program is syntactically correct in TypeScript.
The tsc compiler helps to detect many defects before uploading code to production. Such defects are not always bugs. Sometimes they do not lead to a breach of the terms of reference for a long time, but when new requirements appear on the part of the customer, they cause an unjustified increase in the cost of the work.
Tsc compiler converts TypeScript source code into JavaScript and analyzes the program, trying to find problematic places. TypeScript can create .js files for any version of JavaScript, starting with ES3. The developer can dictate to TypeScript which analysis rules to activate and which to disable.
Differences between TypeScript and JavaScript
First, let`s access the advantages of TypeScript:
- Errors made during code modification are visible immediately, not at runtime.
- TypeScript has interfaces and classes.
- It was created by Anders Hejlsberg, who also developed C#, Turbo Pascal, and Delphi.
- It has open-source code available on GitHub.
- TypeScript makes it faster and easier to write complex solutions that are easier to develop and test later.
- TypeScript has a high compilation speed and is distributed under the Apache license.
Now let's move to 3 main differences between TypeScript and JavaScript.
Strict typing
Data in JS is stored in variables and has some type: string, number, or logical value. In JavaScript, the typing is dynamic. This means that developers can assign a numeric value to a variable first and then, for example, a text value.
TypeScript adds strict typing to the language. Each variable at creation is assigned a certain type - a standard or created by the developer. The developer can create a type within the limits of the language: for example, a number from 1 to 31 to record a day in a month or an array of two elements to record coordinates.
What is "a variable is assigned a type"? This means it can only accept values within that type throughout the script. A variable set as a number will only be a number. The program will generate an error if the developer tries to assign it a string value.
In addition to the primitive types already present in JavaScript (boolean, bigint, null, number, string, symbol, object, and undefined), TypeScript has any (allows any value) and void (functions that have no return).
The object-oriented paradigm
The OOP treats the information it deals with as classes and objects. An object is a complex instance of data, and a class is the "blueprint" from which objects are created. An object has a class, just as a variable has a type.
JavaScript has features that enable OOP, but only partially. The language supports classes and objects, and that's enough for basic actions. But, for example, it does not work with access modifiers - the ability to make some part of a class "open" or "closed" for outside access.
TypeScript supports three modifiers:
- Public - elements with this modifier are accessible from anywhere without any restrictions. This modifier is set by default.
- Private - elements with this modifier are only available from the class where they are defined.
- Protected - elements with this modifier are available from the class in which they are defined and in subclasses/derived classes.
TypeScript adds many OOP features to JS: access modifiers, abstract classes, and other features of the paradigm.
High project speed
TypeScript helps reduce the time it takes to identify and fix bugs that are sometimes hard to find in a dynamic JavaScript environment. With TypeScript, developers can write more understandable and readable code that describes the subject area as much as possible. In this way, the architecture becomes more pronounced.
Where is TypeScript most often used?
TypeScript is often used when working with Angular. If a developer wants to use Angular tools, they must use TypeScript because, with TS, it will be much easier and quicker. Developers can continue to code Angular in JavaScript, but it won't be easy.
Other popular frameworks and libraries are not as categorical, but they all support development in TypeScript. On the one hand, this is not surprising since TypeScript turns into plain JavaScript after compilation. On the other hand, the contributors have spent valuable resources creating type files. Consequently, they see TypeScript as a development strategy.
Many libraries, Redux particularly, have been created in TypeScript first and assembled into npm packages after compiling to JavaScript for the past several versions.
And TypeScript also allows methodical and predictable porting of the codebase from JavaScript. We foresee developers maintaining legacy projects will take advantage of this.
MaybeWorks expertise in TypeScript
The creators of TypeScript aimed to help developers create and develop products for any system that can execute JavaScript and add confidence to developers that the program will execute predictably. And they succeeded.
MaybeWorks is an IT staff augmentation provider with 50+ developers onboard. Our team is proud of developing hundreds of products covering various niches using top-notch frameworks & libraries within the TypeScript/JavaScript tech stack.
Our area of expertise is defined by web development only. We work exceptionally with upscale techs to build powerful apps with enormous flexibility, stability, and long-term support. This is the reason why our choice has fallen on JavaScript/TypeScript.
Feel free to contact us to discuss your web development assistance.
