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JavaScript
Group items by a property
Loop once and collect items in an object keyed by the property.
Example
javascript
const people = [ { name: 'Ada', city: 'London' }, { name: 'Sam', city: 'Paris' }, { name: 'Lee', city: 'London' }, ]; const byCity = {}; for (const person of people) { (byCity[person.city] ??= []).push(person.name); } console.log(byCity);
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Debounce a function
Loop over an object
Remove duplicates from an array
Shuffle an array
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