Lesson overview · Free interview practice

Compiler

Use the TypeScript Compiler API.

Topics in the full lesson
  • Introduction to the TypeScript Compiler API
  • Setting Up the Environment
  • Understanding the Abstract Syntax Tree (AST)
  • Programmatic AST Manipulation
  • Creating Custom Transformers
  • Applying Transformers during Compilation
  • Practical Examples
  • Best Practices
  • Exercises

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TheoryMedium

The TypeScript Language Service

Question

What is the TypeScript Language Service, and why does it matter for the developer experience? How is it different from the tsc command?

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TheoryMedium

Watch Mode and Incremental Compilation

Question

How does TypeScript's watch mode work? What's the difference between watch mode and incremental compilation, and when does each fit?

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TheoryMedium

Project References for Monorepos

Question

What are TypeScript project references, and what problem do they solve in a monorepo? Show the canonical setup.

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TheoryMedium

What `tsc` Does: Type-Checking and Transpilation

Question

What are the two main jobs of the TypeScript compiler? Show the canonical tsc workflow and the most commonly used options.

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Explain your reasoning or try an implementation before comparing answers.

TheoryHard

The Compiler API: Building Custom TypeScript Tools

Question

What is the TypeScript Compiler API, and what kinds of tools does it enable? Show the canonical "walk the AST" pattern.

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