In the following example, Microdata’s itemref attribute is used to add the email property to the Person item (both from a fictive Microdata vocabulary).
<body>
<div itemscope itemtype="http://example.org/Person" itemref="orphan">
<span itemprop="name">Alice</span>
</div>
<div id="orphan" itemprop="email">
[email protected]
</div>
</body>
Is this valid Microdata?
If I understand the "Associating names with items" algorithm correctly, the "itemrefed" properties are not moved but copied, which leaves this "orphan" itemprop without an item parent.
There are three valid cases for itemprop values. The following one seems to come closest:
If the item is not a typed item: a string that contains no "." (U+002E) characters and no ":" (U+003A) characters.
(Which would mean that the orphaned property is not a "defined property name", i.e., it doesn’t belong to the fictive vocabulary anymore (only the "copied" property does).)
But: there is no "item" involved, as there is no itemscope.
So you can’t specify itemprop without a parent itemscope at all? Doesn‘t seem so:
Every HTML element may have an itemprop attribute specified […]
What am I’m missing in the Microdata specification?
Does an itemprop without an itemscope parent create an item?
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