Can't run babel transpiled files with node

Question

Here is the very basic express boilerplate code that I just modified to use es6 import in order to test the transpiling process app.js:

import "babel-polyfill";
import * as express from "express"
var app = express();


app.get('/', function (req, res) {
  res.send('Hello World!');
});

app.listen(3000, function () {
  console.log('Examdple app listening on port 3000!');
});

in .babelrc

{
    "presets": [
     "es2015"
    ],
    "plugins": ["transform-runtime",
      "transform-es2015-classes"]
  }

Resulting transpiled code app-compiled.js:

"use strict";

require("babel-polyfill");

var _express = require("express");

var express = _interopRequireWildcard(_express);

function _interopRequireWildcard(obj) { if (obj && obj.__esModule) { return obj; } else { var newObj = {}; if (obj != null) { for (var key in obj) { if (Object.prototype.hasOwnProperty.call(obj, key)) newObj[key] = obj[key]; } } newObj.default = obj; return newObj; } }

var app = express();

app.get('/', function (req, res) {
  res.send('Hello World!');
});

app.listen(3000, function () {
  console.log('Examdple app listening on port 3000!');
});

//# sourceMappingURL=app-compiled.js.map

Now trying to run /usr/local/bin/node app-compiled.js :

var app = express();
          ^
TypeError: express is not a function

or /usr/local/bin/node app.js

/Users/Documents/Apps_And_Sites/Js_Apps/projectname/app.js:1
(function (exports, require, module, __filename, __dirname) { import "babel-polyfill";
                                                              ^^^^^^

SyntaxError: Unexpected reserved word

Also, when I don't use the polyfill it's the same 'import' error without the encapsulating function.

If this helps, dependencies in package.json:

 "devDependencies": {
    "babel-cli": "^6.9.0",
    "babel-core": "^6.9.1",
    "babel-eslint": "^6.0.4",
    "babel-plugin-syntax-flow": "^6.8.0",
    "babel-plugin-transform-class-properties": "^6.9.1",
    "babel-plugin-transform-flow-strip-types": "^6.8.0",
    "babel-plugin-transform-runtime": "^6.9.0",
    "babel-polyfill": "^6.9.1",
    "babel-preset-es2015": "^6.9.0",
    "eslint-plugin-flowtype": "^2.2.7",
    "flow-bin": "^0.26.0"
  },
  "dependencies": {
    "babel-runtime": "^6.9.2",
    "express": "^4.13.4"
  }
}

In my webstorm ide, I have babel set with these parameters:

Program: node_modules/babel-cli/bin/babel.js

Arguments: --source-maps --out-file $FileNameWithoutExtension$-compiled.js $FilePath$

Output paths to refresh: $FileNameWithoutExtension$-compiled.js:$FileNameWithoutExtension$-compiled.js.map

Why can't node run the babel transpiled code ?

Answer 1

Your import is syntactically correct but wrong for your usage, it should just be:

import express from 'express';