[Solved] Why does this code never print 'Done'? setTimeout(() => { while(true) {} console.log('Done'); }, 0); | Node.js

Node.js - Timers and Scheduling

Why does this code never print 'Done'?

setTimeout(() => {
  while(true) {}
  console.log('Done');
}, 0);

Aconsole.log is inside while loop and never reached

BsetTimeout with 0 delay never runs callbacks

CInfinite loop blocks event loop, so callback never finishes

DSyntax error in callback function

Step-by-Step Solution

Solution:

Step 1: Analyze infinite loop inside callback
The while(true) loop runs forever, blocking the event loop thread.
Step 2: Understand event loop blocking
Because the callback never finishes, console.log('Done') is never executed.
Final Answer:
Infinite loop blocks event loop, so callback never finishes -> Option C
Quick Check:
Blocking infinite loop stops event loop progress [OK]

Quick Trick: Infinite loops block event loop, stopping all callbacks [OK]

Common Mistakes:

Master "Timers and Scheduling" in Node.js

9 interactive learning modes - each teaches the same concept differently

More Node.js Quizzes

Why does this code never print 'Done'?