How do I write angular2 without decorator syntax?

问题:

I'm roughly following JavaScript/TypeScript quickstart for Angular2 to write my app in ES6 but can't get the decoractor to works

entry.js

import * as stylesheet from '../assets/styles/app.scss';

import jQuery from '../node_modules/jquery/dist/jquery';
import $ from '../node_modules/jquery/dist/jquery';
import * as semanticUi from '../node_modules/semantic-ui/dist/semantic';

import '../node_modules/angular2/bundles/angular2-polyfills'
import '../node_modules/rxjs/bundles/Rx.umd'
import '../node_modules/angular2/bundles/angular2-all.umd'

import {bootstrap}    from '../node_modules/angular2/bootstrap'
import {AppComponent} from './app.component'

bootstrap(AppComponent);

app.component.js

import {Component} from '../node_modules/angular2/core';

@Component({
    selector: 'my-app',
    template: '<h1>Hello {{ name }}</h1>'
})
export class AppComponent {
    constructor() {
        this.name = 'Max';
        console.log(this.name);
    }
}

package.json

{
    "scripts": {
        "build:app": "browserify -e ./app/index.js -o ./dist/app.js",
    },
    "devDependencies": {
        "babel-core": "6.3.x",
        "babel-plugin-angular2-annotations": "^3.0.3",
        "babel-plugin-transform-decorators": "^6.3.13",
        "babel-preset-es2015": "6.3.x",
        "babelify": "7.2.x",
        "cpy": "3.4.x",
    },
    "babel": {
        "presets": [
            "es2015"
        ],
        "plugins": [
            "angular2-annotation",
            "transform-decorators"
        ]
    },
    "browserify": {
        "transform": [
            [
                "babelify",
                {
                    "presets": [
                        "es2015"
                    ],
                    "plugins": [
                        "angular2-annotation",
                        "transform-decorators"
                    ]
                }
            ]
        ]
    }
}

Error

npm run build:app

> ng2-app@0.0.2 build:app /data/projects/ng2-app
> browserify -e ./app/index.js -o ./dist/app.js

ReferenceError: Unknown plugin "angular2-annotation" specified in "/data/projects/ng2-app/package.json" at 0, attempted to resolve relative to "/data/projects/ng2-app" while parsing file: /data/projects/ng2-app/app/index.js
    at /data/projects/ng2-app/node_modules/babel-core/lib/transformation/file/options/option-manager.js:193:17
    at Array.map (native)
    at Function.normalisePlugins (/data/projects/ng2-app/node_modules/babel-core/lib/transformation/file/options/option-manager.js:173:20)
    at OptionManager.mergeOptions (/data/projects/ng2-app/node_modules/babel-core/lib/transformation/file/options/option-manager.js:271:36)
    at OptionManager.addConfig (/data/projects/ng2-app/node_modules/babel-core/lib/transformation/file/options/option-manager.js:221:10)
    at OptionManager.findConfigs (/data/projects/ng2-app/node_modules/babel-core/lib/transformation/file/options/option-manager.js:370:30)
    at OptionManager.init (/data/projects/ng2-app/node_modules/babel-core/lib/transformation/file/options/option-manager.js:412:12)
    at File.initOptions (/data/projects/ng2-app/node_modules/babel-core/lib/transformation/file/index.js:191:75)
    at new File (/data/projects/ng2-app/node_modules/babel-core/lib/transformation/file/index.js:122:22)
    at Pipeline.transform (/data/projects/ng2-app/node_modules/babel-core/lib/transformation/pipeline.js:42:16)

npm ERR! Linux 3.13.0-71-generic
npm ERR! argv "/usr/bin/nodejs" "/usr/bin/npm" "run" "build:app"
npm ERR! node v5.3.0
npm ERR! npm  v3.5.3
npm ERR! code ELIFECYCLE

Question

• I don't care about using the decorator syntax, so I can I rewrite this to use ES6/ES2015 instead?

回答1:

You can use ES5 syntax:

import * as ng from 'angular2/core';

const SomeComponent = ng
.Component({ /* ... */})
.View({ /* ... */ })
.Class({
    constructor() {}
});

const SomeDirective = ng
.Directive({ /* ... */ })
.Class({
    constructor() {}
});

So for your case it will be (see this plunk):

export const AppComponent = Component({
  selector: 'my-app',
  template: '<h1>Hello {{ name }}</h1>'
})
.Class({
  constructor() {
    this.name = 'Max';
    console.log(this.name);
  }
});

PS But if I were you, I would try to resolve the problem and continue to use ES7 decorators. Maybe you've forgotten to do npm install?

回答2:

It is because you are using Babel 6 and decorators are currently disabled for it, but you can make it work with the legacy plugin transform-decorators-legacy. The reason for disableing is that the syntax will change in the near future. https://github.com/loganfsmyth/babel-plugin-transform-decorators-legacy