code: function getSelection (field) {
    if (typeof field !== 'object') {
      throw new TypeError('The field must be an object.')
    }
  
    return {
      start: field.selectionStart,
      end: field.selectionEnd
    }
  }
docs: Get the element selection start and end values
  @param  {Element}       field The DOM node element
  @return {SelectionType}       The selection start and end