Data Grouping with Array.prototype.reduce()

Snippet

Data Grouping with Array.prototype.reduce()

The reduce method is a versatile tool for transforming an array into a single object. By initializing with an empty object, we can iterate through the list and dynamically build a categorized map of items.

snippet.js
javascript
const inventory = [
  { name: 'Apples', type: 'fruit' },
  { name: 'Carrots', type: 'vegetable' },
  { name: 'Bananas', type: 'fruit' }
];
 
const grouped = inventory.reduce((acc, item) => {
  const key = item.type;
  if (!acc[key]) acc[key] = [];
  acc[key].push(item.name);
  return acc;
}, {});

Breakdown

inventory.reduce((acc, item) => { ... }, {});

Starts the reduction with an empty object as the accumulator.

const key = item.type;

Determines the category key for the current item.

acc[key].push(item.name);

Appends the item's name to the corresponding category array.

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Data Grouping with Array.prototype.reduce()

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