text: 
  import createMapper from './index'
  
  export default createMapper({
    breakpoints: [ null, 'ns', 'm', 'l' ],
    props: [
      'ma', 'mt', 'mr', 'mb', 'ml', 'mh', 'mv',
      'pa', 'pt', 'pr', 'pb', 'pl', 'ph', 'pv',
      'w',
      'f', 'lh',
      'v',
      'bg',
    ],
    getter: ({ breakpoint, prop, value }) => breakpoint
      ? [ prop, value, '-', breakpoint ].join('')
      : [ prop, value ].join('')
  })
  