JavaScript

prototype chain in JavaScript

JavaScriptPrototypesprototype chainintermediate

What this snippet does

When a property isn't found on an object, JavaScript walks up to its prototype — this is the prototype chain.

Expected output

woof
eating
true
false
true

Why practise typing this

Typing prototypes 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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