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javascriptecmascript-6importes6-modulescommonjs

Is it possible to use ES6 import without creating a variable and execute in a single line, similar to CommonJS?

Just wondering, am I able to import ES6 modules without creating a "placeholder" variable and run it immediately?

for instance, instead of ES6's import that creates an unused express variable:

import express from 'express' 
const app = express();

In CommonJS I can do it without it:

const app = require("express")();

This is particularly useful for one time only imports such as dotenv:

require("dotenv").config();

Instead of 

import dotenv from 'dotenv'
dotenv.config();
//or
import {} from 'dotenv/config'
config()

Which I think CommonJS syntax is much cleaner, but it seems ES6 imports are the future.

Thanks

Solution

  • There's no way for that in ES6, but there's a finshed (Stage 4) proposal for doing this:

    (await import('dotenv')).config()

    Or, if the target module doesn't provide named export:

    (await import('dotenv')).default.config()

    However, you should note that await can only be used inside an async function (until this another proposal gets implemented):

    (async ()=>{
  (await import('dotenv'))/*.default*/.config()
})()