@ngdoc error
@name $compile:tplrt
@fullName Invalid Template Root
@description

When a directive is declared with `template` (or `templateUrl`) and `replace` mode on, the template must have exactly one root element.
That is, the text of the template property or the content referenced by the templateUrl must be contained within a single html element.
For example, '<p>blah <em>blah</em> blah</p>' instead of simply 'blah <em>blah</em> blah'.
Otherwise, the replacement operation would result in a single element (the directive) being replaced with multiple elements or nodes, which is unsupported and not commonly needed in practice.


For example a directive with definition:
```
myModule.directive('myDirective', function factory() {
  return {
    ...
    replace: true,
    templateUrl: 'someUrl'
    ...
  }
});
```

And a template provided at URL `someUrl`. The template must be an html fragment that has only a single root element, like the `div` element in this template:
```
<div><b>Hello</b> World!</div>
```

An an invalid template to be used with this directive is one that defines multiple root nodes or elements. For example:
```
<b>Hello</b> World!
```