vue-loader

webpack loader for Vue Single-File Components

NOTE: The master branch now hosts the code for v15! Legacy code is now in the v14 branch.

What is Vue Loader?

vue-loader is a loader for webpack that allows you to author Vue components in a format called Single-File Components (SFCs):

<template>
  <div class="example">{{ msg }}</div>
</template>

<script>
export default {
  data () {
    return {
      msg: 'Hello world!'
    }
  }
}
</script>

<style>
.example {
  color: red;
}
</style>

There are many cool features provided by vue-loader:

Allows using other webpack loaders for each part of a Vue component, for example Sass for <style> and Pug for <template>;
Allows custom blocks in a .vue file that can have custom loader chains applied to them;
Treat static assets referenced in <style> and <template> as module dependencies and handle them with webpack loaders;
Simulate scoped CSS for each component;
State-preserving hot-reloading during development.

In a nutshell, the combination of webpack and vue-loader gives you a modern, flexible and extremely powerful front-end workflow for authoring Vue.js applications.

How It Works

The following section is for maintainers and contributors who are interested in the internal implementation details of vue-loader, and is not required knowledge for end users.

vue-loader is not a simple source transform loader. It handles each language blocks inside an SFC with its own dedicated loader chain (you can think of each block as a "virtual module"), and finally assembles the blocks together into the final module. Here's a brief overview of how the whole thing works:

vue-loader parses the SFC source code into an SFC Descriptor using @vue/component-compiler-utils. It then generates an import for each language block so the actual returned module code looks like this:
``` js
// code returned from the main loader for 'source.vue'
// import the block
import render from 'source.vue?vue&type=template'
// import the