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TypeScript Quiz Practice
Active Recall Drill Session
← Exit Session
Question 1 of 1
easy
TypeScript
What does over-annotating obviously-inferred local variables (like `const isLoading: boolean = false`) actually cost?
A
Real runtime performance
B
Nothing functionally — it's just unnecessary code noise, since inference would produce the exact same type without it
C
It causes a compile error
D
It disables type-checking for that variable
Check Answer