SyntaxError: 'import' 和 'export' 可能只出现在 'sourceType: module' 中 - Gulp

考虑以下两个文件:

app.js

import Game       from './game/game';
import React      from 'react';
import ReactDOM   from 'react-dom';

export default (absPath) => {
  let gameElement = document.getElementById("container");

  if (gameElement !== null) {
      ReactDOM.render(
          <Game mainPath={absPath} />,
          gameElement
      );
  }
}

index.js

import App from './src/app';

gulpfile.js

var gulp        = require('gulp');
var source      = require('vinyl-source-stream');
var browserify  = require('browserify');
var babelify    = require("babelify");
var watch       = require('gulp-watch');

gulp.task('make:game', function(){
  return browserify({
    entries: [
      'index.js'
    ]
  })
  .transform('babelify')
  .bundle()
  .pipe(source('index.js'))
  .pipe(gulp.dest('app/'));
});

错误:

gulp make:game
[13:09:48] Using gulpfile ~/Documents/ice-cream/gulpfile.js
[13:09:48] Starting 'make:game'...

events.js:154
      throw er; // Unhandled 'error' event
      ^
SyntaxError: 'import' and 'export' may appear only with 'sourceType: module'

这是什么错误?我做错了什么?

推荐答案

旧版本的 Babel 提供了开箱即用的一切.较新的版本要求您安装安装所需的任何插件.首先，您需要安装 ES2015 预设.

npm install babel-preset-es2015 --save-dev

return browserify({ ... })
  .transform(babelify.configure({
    presets: ["es2015"]
  }))
  ...