What is TypeScript?
TypeScript is JavaScript which is designed to scale web applications.
As an object-based scripting language, JavaScript is designed by Netscape in 1995. It has an open standard (ECMAScript) and a huge developer community.
TypeScript is an object-oriented language designed by Microsoft in 2012. It is a superset of JavaScript and can be used both a language and a set of tools. It provides optional static typing, which can help to catch errors as they appear making it ideal for large team collaborations.
Advantages
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TypeScript can point out compilation errors at the time of development.
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It, as mentioned above, offers static typing which allows catching type errors at compile time and therefore gives a less painful development experience.
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It is great for large team collaborations.
- Perhaps the biggest feature that TypeScript provides is type-checking, which can prevent bugs such as the one below:
// TypeScriptfunction fetchUserID(isUser: boolean) : string {if (isUser) {return '94321';}return 'username not present';}// throws: error TS2345: Argument of type '"true"'// is not assignable to parameter of type 'boolean'.let userId = fetchUserID('true');
In the above code, we are passing a string to fetchUserID() function which is expecting a boolean variable. So, it will throw an exception:
Argument of type true is not assignable to the parameter of type boolean.
Sections of TypeScript
TypeScript has the following three sections:
Language: It is an object-oriented language which can be broadly divided into three things:
- Syntax
- Keywords
- Type Annotations
TypeScript compiler: Translates the instructions written in TypeScript to JavaScript.
TypeScript language service: Supports editor operations such as:
- Statement completion
- Code formatting
- Colorization
