不正确的coffeescript编译

使用此代码

咖啡脚本

A 类构造函数： (@name, @age) ->

放弃它

var A;

A = class A {
  constructor(name, age) {
    this.name = name;
    this.age = age;
  }

};

之前

var A;

A = (function() {
  function A(name, age) {
    this.name = name;
    this.age = age;
  }

  return A;

})();

如何返回这种编译变体？

这是package.json

{
  "name": "gulp.dev",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "",
  "license": "ISC",
  "devDependencies": {
    "browser-sync": "^2.23.6",
    "coffee-script": "^1.12.7",
    "gulp": "^3.9.1",
    "gulp-autoprefixer": "^4.1.0",
    "gulp-cached": "^1.1.1",
    "gulp-coffee": "^3.0.2",
    "gulp-coffeescript": "0.0.15",
    "gulp-concat": "^2.6.1",
    "gulp-debug": "^3.2.0",
    "gulp-group-css-media-queries": "^1.2.2",
    "gulp-notify": "^3.2.0",
    "gulp-remember": "^1.0.1",
    "gulp-sass": "^3.1.0",
    "gulp-sourcemaps": "^2.6.4",
    "smart-grid": "^2.0.1"
  }
}

和gulpfile.js

const gulp          = require('gulp');
const browserSync   = require('browser-sync').create();
const concat        = require('gulp-concat');
const debug         = require('gulp-debug');
const sourcemaps    = require('gulp-sourcemaps');
const autoprefixer  = require('gulp-autoprefixer');
const remember      = require('gulp-remember');
const cached        = require('gulp-cached');
const notify        = require("gulp-notify");

const sass          = require('gulp-sass');
const coffee        = require('gulp-coffee');

const gcmq          = require('gulp-group-css-media-queries');


gulp.task('sass', function(){
    gulp.src('./source/style.sass')

    .pipe(cached('sass'))
    .pipe(remember('sass'))
    .pipe(debug({title: "sass"}))
    .pipe(sass({outputStyle: 'expanded'})).on('error', notify.onError())
    .pipe(gcmq())
    .pipe(gulp.dest('./production/css/')).resume()
});

gulp.task('coffee', function(){
     gulp.src('./source/main.coffee')

    .pipe(cached('coffee'))
    .pipe(remember('coffee'))
    .pipe(debug({title: "coffee"}))
    .pipe(coffee({bare: true})).on('error', notify.onError())
    .pipe(gulp.dest('./production/js/')).resume()
});


gulp.task('autoprefixer', function () {
    gulp.src('production/css/style.css')
    .pipe(autoprefixer({
        browsers: ['last 5 versions'],
        cascade: false
    }))
    .pipe(gulp.dest('production/css/'));
});

gulp.task('watch', function(){
    gulp.watch("./source/style.sass", ['sass'])
    gulp.watch("./source/main.coffee", ['coffee'])
    gulp.watch("production/css/style.css", ['autoprefixer'])
});


gulp.task('serve', function() {

    browserSync.init({
        proxy: "gulp.su"

    });
    browserSync.watch("*.*").on('change', browserSync.reload);
    browserSync.watch("./production/**/*.*").on('change', browserSync.reload);
});

gulp.task('default', ['watch', 'serve']);