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Demo 4.16

Diagnosing bugs

Files in this demo

├─ index.html
├─ style.css
└─ script.js

This demo is broken! There are 4 bugs hiding in script.js. When it works, the text should say “Ready to click!” and turn big, red, and highlighted when you click the button.

How to diagnose a bug:

  1. 1Open the console. Bugs show up as red error messages.
  2. 2Read the error. It tells you what went wrong and which line it happened on.
  3. 3Fix one bug at a time. One error can hide others, so new errors may appear as you fix old ones.

Common bugs include typos, missing quotes, missing brackets, and mismatched capitalization.

Stuck? Check the next demo for the answers.

Next demoDiagnosing bugs (fixed)
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