code: function transform(string, source, options) {
    // order of transformation is important
  
    try {
      if (options.rebeccapurple && string.indexOf("rebeccapurple") > -1) {
        string = transformRebeccapurple(string, source)
      }
  
      if (options.hwb && string.indexOf("hwb(") > -1) {
        string = transformHwb(string, source)
      }
  
      if (options.hexAlpha && string.indexOf("#") > -1) {
        string = transformHexAlpha(string, source)
      }
  
      if (options.color && string.indexOf("color(") > -1) {
        string = transformColor(string, source)
      }
    }
    catch (e) {
      throw new Error(gnuMessage(e.message, source))
    }
  
    return string
  }
docs: Transform colors to rgb() or rgba() on a declaration value
  
  @param {String} string
  @return {String}