JavaScript

private fields in JavaScript

JavaScriptClassesprivate fieldsintermediate

What this snippet does

Private class fields with # are enforced by the engine — they cannot be accessed or patched from outside the class.

Expected output

70

Why practise typing this

Typing classes 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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