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Conditional Types
advancedtypescript
Background
Conditional types enable powerful type-level programming for library authors and advanced TypeScript users.
Problem
Create conditional types that extract or transform types based on conditional logic at the type level.
Input
Type definitions
Output
Conditionally selected types
Sample tests
Sample 1
Input: NonNullable<string | null>
Expected: string
Your solution
Learning objective
Master type-level programming and conditional types