What this snippet does
Object keys collide with prototype properties like toString — Map has no such issue and allows any value as a key.
Expected output
overridden! safe function as key 2
Why practise typing this
Typing map 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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