BeginnerLesson 5 of 1825 min 路 hands-on
Functions
Part of the TypeScript course
Functions are where most of the bugs live and where types pay off the most. A function's signature (its parameters and its return type) is a contract between the caller and the body. TypeScript lets you write that contract down and checks both sides.
In a function declaration, each parameter gets its own type. ...
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Start this lessonFunctionsWhat you'll learn
- Parameter types
- Return types
- Void return
- Default parameters
- Rest parameters
- Function type expressions
- Arrow functions
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All lessons in this course
18 lessons- 1Hello, TypeScript20 min
- 2Type Basics25 min
- 3Arrays and Tuples25 min
- 4Object Types and Interfaces25 min
- 5Functions25 min
- 6Union and Literal Types25 min
- 7Type Narrowing30 min
- 8Type Aliases vs Interfaces20 min
- 9Optional, Readonly, and Nullable25 min
- 10Enums20 min
- 11Generics30 min
- 12Classes25 min
- 13Inheritance and Abstract Classes25 min
- 14Modules25 min
- 15Utility Types30 min
- 16Mapped and Conditional Types30 min
- 17Declaration Files and Libraries25 min
- 18tsconfig and the Compiler30 min
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