piping-loaders.webpack.config.js

// works in both v1 and v2
{
  test: /\.less$/,
  loader: "style-loader!css-loader!less-loader"
}

// works in v2
{
  test: /\.less$/,
  use: [
    'style-loader',
    'css-loader',
    'less-loader'
  ]
}

// does not work in v2 (results in: Module not found: Error: Can't resolve 'style-loader!css-loader!less-loader')
{
  test: /\.less$/,
  use: {
    loader: "style-loader!css-loader!less-loader"
  }
}

// doesn't work in v2 (results in: Module not found: Error: Can't resolve 'style!css!less')
{
  test: /\.less$/,
  use: "style!css!less"
}

// doesn't work in v2 (results in: Module not found: Error: Can't resolve 'style-loader!css-loader!less-loader')
{
  test: /\.less$/,
  use: "style-loader!css-loader!less-loader"
}

// doesn't work in v2 (results in: Module not found: Error: Can't resolve 'style!css!less')
{
  test: /\.less$/,
  use: {
    loader: "style!css!less"
  }
}

{
  test: /\.less$/,
  use: {
    loader: "style-loader!css-loader!less-loader"
  }
}

needs to be changed to

{
  test: /\.less$/,
  use: "style-loader!css-loader!less-loader"
}

Also the rest don't work because webpack latest requires explicit loader name resolution. So instead of babel you must specify babel-loader.

@TheLarkInn: One of the examples I had in the gist was the exact example you gave. I tried again, once more copy/pasting your code, and build doesn't work. Exception thrown, when importing a .less file is: Module not found: Error: Can't resolve 'style-loader!css-loader!less-loader'

The configs that do work are either:

// legacy style
{
  test: /\.less$/,
  loader: "style-loader!css-loader!less-loader"
}

// chain via array of loader names
{
  test: /\.less$/,
  use: [
    'style-loader',
    'css-loader',
    'less-loader'
  ]
}

// chain via array of loader names and objects
{
  test: /\.less$/,
  use: [
    'style-loader',
    { loader: 'css-loader', options: { importLoaders: 1 } },
    'less-loader'
  ]
}

Do you want me to create an issue about this, if ! chaining should work? I'm using webpack@v2.2.0-rc.3?