Typescript is a statically typed superset of JavaScript that adds static types, classes and interfaces to the language, enhancing code quality and understandability. This object oriented programming language is essential in modern web development and plays an integral role in building large scale applications. In tech interviews, knowledge of Typescript often is tested to evaluate a candidate’s ability to write more robust code, detect errors at compile-time and handle more complex coding structures used in software architecture. This post will guide you through Typescript interview questions and answers to help you prepare.
TypeScript Fundamentals
- 1.
What is TypeScript and how does it differ from JavaScript?
Answer:TypeScript is a statically-typed superset of JavaScript, developed and maintained by Microsoft. It enables enhanced code maintainability and predictability. After compiling, TypeScript code is transpiled into standard, browser-compatible JavaScript.
Key distinctions between TypeScript and JavaScript include the use of type annotations, the ability to work with existing JavaScript code, and more.
TypeScript Features & Benefits
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Type System: Offers static typing, allowing developers to define the type of variables, parameters, and return values. This helps catch errors during development, reducing runtime issues.
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Advanced Language Features: Incorporates modern ECMAScript syntax and features, often before they are rolled out in JavaScript. Additionally, TypeScript brings functional programming patterns, classes, and access modifiers (such as
publicandprivate) -
Compatibility with JavaScript: TypeScript can interpret existing JavaScript code with minor or no modifications.
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Tooling and Extra Safety: Provides enhanced autocompletion, refactoring, and documentation via TypeScript-aware tools. TypeScript helps catch and rectify common programming errors without needing to run the code.
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ECMAScript Compatibility: TypeScript allows developers to target different ECMAScript versions, ensuring the generated JavaScript is compatible with the targeted browsers.
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Code Structure & Readability: Promotes maintainability by enforcing a defined coding structure and fostering code clarity.
TypeScript’s Role in Modern Development
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Workplace Adaptability: TypeScript is used in an extensive range of projects, from small utilities to large-scale applications.
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Community Support: Supported by a vibrant developer community, TypeScript benefits from frequent updates, bug fixes, and useful extensions.
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On-Going Development: A robust language server furnishes accurate tooling feedback, such as linting and error suggestions in real time.
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Rapid Enhancement: The TypeScript team consistently introduces new features and reinforces existing ones.
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- 2.
Can you explain what is meant by “TypeScript is a superset of JavaScript”?
Answer: - 3.
What are the basic types available in TypeScript?
Answer: - 4.
How do you declare variables in TypeScript?
Answer: - 5.
What are Interfaces in TypeScript and how do they work?
Answer: - 6.
Describe the Enum type and when you might use it.
Answer: - 7.
How do you define and use a function in TypeScript?
Answer: - 8.
What does “type inference” mean in the context of TypeScript?
Answer: - 9.
Explain the use of ‘let’ and ‘const’ in TypeScript.
Answer: - 10.
How do you compile TypeScript files into JavaScript?
Answer:
Explore all 100 TypeScript questions and more Web and Mobile Dev topicsTypeScript Classes and Objects
- 11.
Explain classes in TypeScript. How are they different from ES6 classes?
Answer: - 12.
How do you implement Inheritance in TypeScript?
Answer: - 13.
What are access modifiers and how do they work in TypeScript?
Answer: - 14.
Discuss Abstract classes and their purposes in TypeScript.
Answer: - 15.
Can you describe the use of Constructors within TypeScript classes?
Answer:
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