Code Typing · JavaScript
Group By
Group array items by a key extractor function.
Difficulty: Beginner · 12 Lines · License: public-domain
function groupBy(items, keyFn) {
const groups = {};
for (const item of items) {
const key = keyFn(item);
if (!groups[key]) groups[key] = [];
groups[key].push(item);
}
return groups;
}Time0:00
Speed (WPM)0.0
Accuracy100.0%
Mistakes0
Live Keyboard
Next Key: F | Last Pressed: -
Progress: 0.0%
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