DeepFrontend
Learning Paths
Practice
System Design & DS
Design Studio
Data Structures Curriculum
Real-World Case Studies
Careers
Job Board
Resume Builder
Blog
Sign in
Search
⌘K
Go Pro
Loading compiler resources...
TypeScript Quiz Practice
Active Recall Drill Session
← Exit Session
Question 1 of 1
easy
TypeScript
What does a mapped type like `{ [K in keyof T]: T[K] }` do?
A
Nothing, it's invalid syntax
B
Iterates over every key of T, producing a new property for each, optionally transforming the value type or adding modifiers along the way
C
Only works on arrays
D
Removes all properties from T
Check Answer