TS.01.03 JuniorCore — asked often

any, unknown, never and void

Comes up in: Recruiter screen

This concept is being written. It gets the full five steps — explanation, predict, interview angle, practice with tests, and review cards. Here is exactly what it will cover, so you can study it elsewhere in the meantime.

What it covers

any disables checking (and spreads)
unknown must be narrowed
never as the empty type (exhaustiveness, functions that throw)
void vs undefined in callbacks
catch variables are unknown under strict

Words you will know

top typebottom typenever

What you will practise

replace 6 anys safely

Interview questions this answers

What is the difference between any, unknown and never?