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TypeScript

TypeScript Types

Basic and advanced type annotations

Basic Types

8 items

Command	Description
`string`	Text values
`number`	Numeric values
`boolean`	true / false
`any`	Disable type checking (avoid)
`unknown`	Safer any
`void`	No return value
`null / undefined`	Empty values
`never`	Unreachable code

Arrays & Tuples

3 items

Command	Description
`string[]`	Array of strings
`Array<number>`	Array of numbers (generic)
`[string, number]`	Tuple (fixed length & types)

Union & Intersection

3 items

Command	Description
`string \| number`	Union (either type)
`TypeA & TypeB`	Intersection (merged types)
`type Status = "success" \| "error"`	Liteal union

Defining Types

3 items

Command	Description
`type User = { name: string }`	Type alias
`interface User { name: string }`	Interface
`enum Role { ADMIN, USER }`	Enum