IIFE module in JavaScript

What this snippet does

The module pattern uses an IIFE to hide private variables and expose only a controlled public API.

Expected output

4
2.5

Why practise typing this

Typing modules code builds muscle memory for the symbols and indentation JavaScript uses most, which prose-based typing tests never cover. DevType measures your words per minute and accuracy on this snippet and tracks the individual characters you mistype, so later lessons can target them.

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