30-seconds-of-code/snippets/toPairs.md

title, tags, expertise, author, firstSeen, lastUpdated

title	tags	expertise	author	firstSeen	lastUpdated
Object to pairs	object,array	intermediate	chalarangelo	2020-03-23T15:07:23+02:00	2020-10-22T20:24:30+03:00

Creates an array of key-value pair arrays from an object or other iterable.

• Check if Symbol.iterator is defined and, if so, use Array.prototype.entries() to get an iterator for the given iterable.
• Use Array.from() to convert the result to an array of key-value pair arrays.
• If Symbol.iterator is not defined for obj, use Object.entries() instead.

const toPairs = obj =>
  obj[Symbol.iterator] instanceof Function && obj.entries instanceof Function
    ? Array.from(obj.entries())
    : Object.entries(obj);

toPairs({ a: 1, b: 2 }); // [['a', 1], ['b', 2]]
toPairs([2, 4, 8]); // [[0, 2], [1, 4], [2, 8]]
toPairs('shy'); // [['0', 's'], ['1', 'h'], ['2', 'y']]
toPairs(new Set(['a', 'b', 'c', 'a'])); // [['a', 'a'], ['b', 'b'], ['c', 'c']]