How to define scripts for npm command?
<p>I am using npm+webpack to manage a react web application. And I want to define a few command for npm in order to run some webpack command. Below is the two command scripts I defined in package.json file.</p>

<pre><code>"scripts": {
"start": "webpack-dev-server --host 0.0.0.0",
"build": "NODE_ENV=production webpack --config ./webpack.config.js --progress --profile --colors"
},
</code></pre>

<p>As you can see, there are two commands 'start' and 'build'. When I run <code>npm start</code> it will run <code>webpack-dev-server --host 0.0.0.0</code> to launch a web server. 
But when I run <code>npm build</code>, it doesn't run the configured command and simply returns without any output. I wander how to define a script command for npm to use. Below is my whole package.json file:</p>

<pre><code>{


"name": "demo",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "start": "webpack-dev-server --host 0.0.0.0",
    "build": "NODE_ENV=production webpack --config ./webpack.config.js --progress --profile --colors"
  },
  "author": "",
  "license": "ISC",
  "devDependencies": {
    "babel-core": "^6.9.0",
    "babel-loader": "^6.2.4",
    "compression-webpack-plugin": "^0.3.1",
    "css-loader": "^0.23.1",
    "less": "^2.7.1",
    "less-loader": "^2.2.3",
    "npm-install-webpack-plugin": "^3.1.3",
    "style-loader": "^0.13.1",
    "svg-sprite-loader": "0.0.26",
    "webpack": "^1.13.1",
    "webpack-dev-server": "^1.14.1",
    "webpack-shell-plugin": "^0.4.2"
  },
  "dependencies": {
    "actions": "^1.3.0",
    "axios": "^0.12.0",
    "babel-preset-stage-2": "^6.11.0",
    "cdnjs": "^0.3.2",
    "components": "^0.1.0",
    "containers": "0.0.1",
    "extract-text-webpack-plugin": "^1.0.1",
    "features": "^0.1.0",
    "file-loader": "^0.8.5",
    "fo": "^0.1.1",
    "jshint": "^2.9.2",
    "jshint-loader": "^0.8.3",
    "leaflet": "^0.7.7",
    "material-ui": "^0.15.2",
    "moment": "^2.13.0",
    "normalize.css": "^3.0.2",
    "nuka-carousel": "^2.0.0",
    "public": "^0.1.2",
    "query-string": "^4.2.2",
    "react": "^15.1.0",
    "react-addons-css-transition-group": "^15.1.0",
    "react-addons-shallow-compare": "^15.1.0",
    "react-alert": "^1.0.14",
    "react-button": "^1.2.1",
    "react-cookie": "^0.4.7",
    "react-date-picker": "^5.3.9",
    "react-datepicker": "^0.27.0",
    "react-dom": "^15.0.2",
    "react-infinite-calendar": "^1.1.14",
    "react-redux": "^4.4.5",
    "react-router": "^2.4.1",
    "react-router-redux": "^4.0.5",
    "react-select": "^1.0.0-beta13",
    "react-spinkit": "^1.1.8",
    "react-tap-event-plugin": "^1.0.0",
    "react-tappable": "^0.8.1",
    "redux": "^3.5.2",
    "redux-thunk": "^2.1.0",
    "sha1": "^1.1.1",
    "source-map-loader": "^0.1.5",
    "src": "^1.1.2",
    "style": "0.0.3",
    "url-loader": "^0.5.7",
    "utils": "^0.3.1"
  }
}
</code></pre>