How to Efficiently Extract Specific Properties from an Object in ES6?

One-liner to Take Some Properties from Object in ES6

Problem:

The goal is to create a concise function in ES6 that extracts specific properties from an object. A solution involving destructuring and simplified object literals is presented, but concerns arise regarding the repetition of field lists.

Answer:

To achieve a slimmer solution, consider using parameter destructuring to eliminate the need for an explicit parameter:

({id, title}) => ({id, title})

While parameter destructuring is convenient, it still requires repeating the property list. For a more general solution, employ the following:

function pick(o, ...props) {
    return Object.assign({}, ...props.map(prop => ({[prop]: o[prop]})));
}

This solution utilizes Object.assign to merge objects while preserving specified properties (props).

Additional Considerations for Property Attributes:

If it's crucial to retain the attributes of the original properties (such as configurability and getters/setters), and exclude non-enumerable properties, consider the following:

function pick(o, ...props) {
    var has = p => o.propertyIsEnumerable(p),
        get = p => Object.getOwnPropertyDescriptor(o, p);

    return Object.defineProperties({},
        Object.assign({}, ...props
            .filter(prop => has(prop))
            .map(prop => ({prop: get(props)})))
    );
}

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