Online Diff Tool

A diff tool shows you the differences between two pieces of text. If the program you copied from the book isn't working, you can copy/paste it here to see any differences between your code and the code in the book.

Common errors include missing commas, unclosed string quotes, or uneven indentation.

NOTE: This page is for the 4th edition (with a snake on the cover). If you want to compare your code to the 3rd edition (with a dragon on the cover) book, use the 3rd edition diff tool.

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Copy and paste your code here: