ES7 async expects babel-loader loader function

Question

I am trying to run async waiting functions in JavaScript using the babel webpack loader. I am using the following configuration:

{
  name: 'client',
  context: path.join(__dirname, 'src', 'static', 'scripts'),
  entry: {
    index: './index.js'
  },
  output: {
    path: path.join(__dirname, 'src', 'static', 'bundles'),
    filename: '[name].js'
  },
  module: {
    loaders: [
      {
        test: /\.js$/,
        loader: 'babel',
        query: {
          presets: ['es2015', 'stage-0']
        }
      }
    ]
  },
  resolve: {
    root: path.join(__dirname),
    fallback: path.join(__dirname, 'node_modules'),
    modulesDirectories: ['node_modules'],
  }
}

but it continues to cause an error with the following message:

Module build error: Error: ./ src / static / scripts / index.js: Expected type "Identifier" with option {}

My index.js has this content:

console.log('hi from app');

async function hello() {
  return Promise.resolve('hi')
}

async function conversation () {
  const hi = await hello()
  console.log(hi);
}

Answer 1

It sounds like you got a mistake . It seems to be resolved, but not yet released.

If you cannot wait for its release, you can apply the fix corresponding to commit , which solves the problem.

:

diff (visit.patch ) . git apply visit.patch.

---

From 940b86dadbd0151c33c02e89f0b5ff61077c9214 Mon Sep 17 00:00:00 2001
From: Henry Zhu <[e-mail]>
Date: Thu, 5 Nov 2015 20:10:15 -0500
Subject: [PATCH] transform-regenerator: set node.id to an identifier if null -
 fixes #2835

---
 packages/babel-plugin-transform-regenerator/lib/visit.js | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/node_modules/babel-preset-es2015/node_modules/babel-plugin-transform-regenerator/lib/visit.js b/node_modules/babel-preset-es2015/node_modules/babel-plugin-transform-regenerator/lib/visit.js
index 0f68ffc..c4a0d2e 100644
--- a/node_modules/babel-preset-es2015/node_modules/babel-plugin-transform-regenerator/lib/visit.js
+++ b/node_modules/babel-preset-es2015/node_modules/babel-plugin-transform-regenerator/lib/visit.js
@@ -146,6 +146,10 @@ function getOuterFnExpr(funPath) {
   var node = funPath.node;
   t.assertFunction(node);

+  if (!node.id) {
+    node.id = funPath.scope.parent.generateUidIdentifier("callee");
+  }
+
   if (node.generator && // Non-generator functions don't need to be marked.
       t.isFunctionDeclaration(node)) {
     var pp = funPath.findParent(function (path) {
@@ -171,9 +175,7 @@ function getOuterFnExpr(funPath) {
     );
   }

-  return node.id || (
-    node.id = funPath.scope.parent.generateUidIdentifier("callee")
-  );
+  return node.id;
 }

 function getRuntimeMarkDecl(blockPath) {

---

Update:

, ​​, . , , .

Answer 2

-, , babel:

npm i -D babel-loader babel-polyfill babel-preset-es2015 babel-preset-stage-0 babel-runtime

( , babel-runtime - YMMV)

entry - :

  entry: [
    'babel-polyfill',
    './index.js'
  ]

babel-polyfill script, " ", async/wait.

babel-loader module ( babel)

  module: {
    loaders: [
      {
        test: /\.js$/,
        exclude: /(node_modules|bower_components)/,
        loader: 'babel-loader',
        query: {
          presets: [
            'es2015',
            'stage-0'
          ]
        }
      }
    ]

.

. Node , require('babel-polyfill'); script, , aync/await.

es2015 stage-0 polyfill Node 5 - .babelrc

{
  "presets": [
    "node5"
  ]
}

node5 - babel. polyfill Node 5.x, . Node 4.x( ES6).

NPM:

npm i -D babel-preset-node5