Javascript Slugify

slugify.js

function slugify (text, ampersand = 'and') {
  const a = 'àáäâèéëêìíïîòóöôùúüûñçßÿỳýœæŕśńṕẃǵǹḿǘẍźḧ'
  const b = 'aaaaeeeeiiiioooouuuuncsyyyoarsnpwgnmuxzh'
  const p = new RegExp(a.split('').join('|'), 'g')

  return text.toString().toLowerCase()
    .replace(/[\s_]+/g, '-')          // Replace whitespace and underscore with single hyphen
    .replace(p, c =>
      b.charAt(a.indexOf(c)))         // Replace special chars
    .replace(/&/g, `-${ampersand}-`)  // Replace ampersand with custom word
    .replace(/[^\w-]+/g, '')          // Remove all non-word chars
    .replace(/--+/g, '-')             // Replace multiple hyphens with single
    .replace(/^-+|-+$/g, '')          // Remove leading and trailing hyphens
}