Yeoman

https://stackoverflow.com/questions/19485806/what-does-mean-in-paths-of-gruntfile-js

What does `{,*/}` mean in paths of Gruntfile.js?

watch: {
    styles: {
      files: [
        '<%= yeoman.app %>/styles/{,*/}*.less'
      ],
      tasks: ['copy:styles', 'autoprefixer']
    }
}

This pattern is widely used in yeoman templates: it means to look only one level deep inside folder hierarchy. It is used mostly for performance reasons since watching too many files simultaneously can be slow (or even impossible).