What this snippet does
Spread copies top-level properties — later keys override earlier ones, but nested objects are still shared by reference.
Expected output
{ x: 1, y: 2 }
{ x: 99, y: 2, z: 3 }
{ x: 1, y: 20, w: 4 }Why practise typing this
Typing objects 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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