javascript / intermediate
Snippet
Transforming Pairs into Objects with fromEntries
Object.fromEntries transforms a list of key-value pairs into an object. It is the inverse of Object.entries and is extremely useful for transforming data or converting Map instances into plain objects.
snippet.js
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const entries = [['role', 'editor'],['level', 5]];const userConfig = Object.fromEntries(entries);console.log(userConfig.role);const updated = Object.fromEntries(Object.entries(userConfig).map(([k, v]) => [k, String(v).toUpperCase()]));
Breakdown
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Object.fromEntries(entries)
Converts an array of arrays into a standard JavaScript object.
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Object.entries(userConfig)
Breaks the object back into an iterable array of [key, value] pairs.
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.map(([k, v]) => [k, ...])
Allows for easy manipulation of both keys and values during the transformation process.