app.directive('dataFactoryModal', ['$compile', '$timeout', function($compile, $timeout) {
    return {
        scope: { .... }
        link: function (scope, element, attrs) {
            var html = '
               <input ng-model = "recipients" name = "email" type = "text" placeholder = "Enter email(s)" >
               ....
               // Modal button section
               <button type = "button" class = "btn btn-primary" data-factory = "{{dataFactoryCodes}}" data-recipients = "">Submit</button>
               ....
            ';
            ....
        }
    }
}

<button type = "button" class = "btn btn-primary" data-factory = "123;109;129" data-recipients = "meme@email.com;yayaya@email.com">Submit</button>

<button type = "button" class = "btn btn-primary" data-factory = "{{dataFactoryCodes}}" data-recipients = "{{recipients}}">Submit</button>

scope.replaceCommas = function(value) {
   if (value!==undefined) {
      return value.replace(',', ';');
   }
}

data-list = {{replaceCommas(recipients)}}

data-list = "email@email.com;email2@email.com,email3@email.com"

scope.$watch('recipients', function(newValue, oldValue) {
     scope.email = newValue;

     // if I did this, this would replace all commas with semicolons on the button attribute AND on the textfield
     scope.email = newValue.replace(',', ';');

     // if I did this, this would just replace only the first comma
     scope.emailTags = newValue.replace(',', ';');
}

data-list = {{emailTags}}