webpack

content.js

require('./const.js');

console.log('this is content');

gulpfile.js

var gulp = require('gulp'),
    gutil = require("gulp-util"),
    webpack = require("webpack"),
    webpackConfig = require("./webpack.config.js");

gulp.task('default', function (cb) {
    webpack(Object.create(webpackConfig), function(err, stats) {
        if(err) throw new gutil.PluginError("webpack:build", err);
        gutil.log("[webpack:build]", stats.toString({
            colors: true
        }));
    });
});

header.js

require('./lib/typeahead.js');
require('./const.js');

console.log('this is header');

package.json

{
    "name": "",
    "version": "",
    "devDependencies": {
        "jquery": "^1.12.4",
        "webpack": "^1.13.1"
    }
}

webpack.config.js

const webpack = require('webpack');
const dir = './dev/js/';

module.exports = {
    entry: {
        index : [dir + 'header.js'],
        page  : [dir + 'header.js', dir + 'content.js'],
        list  : [dir + 'header.js', dir + 'list.js'],
    },
    output: {
        filename: '[name].js',
        path: './bundle/'
    },
    plugins: [
        new webpack.ProvidePlugin({
            $: "jquery",
            jQuery: "jquery",
            "window.jQuery": "jquery"
        }),
        new webpack.optimize.UglifyJsPlugin({
            compress: {
                warnings: false,
            },
            output: {
                comments: false,
            },
        }),
    ],
 };