m-a-r-c-e-l-i-n-o m-a-r-c-e-l-i-n-o - 1 year ago 100
Javascript Question

Destructuring assignment within import statements

According to this source and a vague memory of having seen this sort of usage in a project somewhere, I'm curious if anyone has been able to do the following:

import {map: { series }} from 'contra'

As stated on this destructuring assignment overview:

The import statement in ES6 behaves similarly to destructuring, but it
is important to note that it is not actually destructuring.

It appears that imports work a little different and perhaps one cannot expect the same exact behavior, but I haven't been able to verify the status of this. Is what I am trying to do part of the official ECMAScript 6/7 spec?

In attempting to answer this, please kindly include (or link) the portion of the spec that clarifies this concern.

Answer Source

The relevant portion of the spec is here.

An ImportDeclaration is

import ImportClause FromClause;

If you examine ImportClause, you'll see it's just the familiar * as Foo, or DefaultImport, or {ImportSpecifier, ...}, etc., where ImportSpecifier is an ImportBinding, which in turn is a BindingIdentifer, which is just a plain old Identifier.

The MDN entry is somewhere between misleading and completely wrong. It should have said (and now does say):

The import statement in ES6 has a superficial resemblance to destructuring, but is actually completely unrelated.

I find more and more incorrect and misleading information in MDN these days. It should be taken with a grain of salt. The authoritative reference is the spec.

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