When you create a new property that has a Page (or Text, or possibly other values) that can be assigned to a wide range of values, it might be nice to restrict those values to a particular subset so that typos don't render the property useless. This has been done on the [[Property:Is used in domain|Is used in domain]] and the [[Property:Is located in facility|Is located in facility]] properties.
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When you create a new property that has a Page (or Text, or possibly other values) that can be assigned to a wide range of values, it might be nice to restrict those values to a particular subset so that typos don't render the property useless. This has been done on the [[Property:Is used in domain|Is used in domain]] and the [[Property:Is located in facility|Is located in facility]] properties. You will see a special property added to those property pages called [https://www.semantic-mediawiki.org/wiki/Help:Special_property_Allows_value_list Allows value list]. The [[https://www.semantic-mediawiki.org/wiki/Help:Special_property_Allows_value_list help link] provides all of the pertinent information, but of special importance is the following:
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<nowiki>Two steps have to be taken to use this special property:
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Add [[Allows value list::...]] to a property page for defining a page reference, e.g. [[Allows value list::Foo]] will define page "MediaWiki:Smw_allows_list_Foo".
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Add permissible values as listed items starting either with "*" or "**" to the "MediaWiki:Smw_allows_list_..." page, e.g. "* Bar" or "** Foobar" to page "MediaWiki:Smw_allows_list_Foo".</nowiki>
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However, might want to go one step further and auto-generate this list from our own properties. For instance, all of our domains are marked with the [Property:Is domain] and our facilities are marked with the [Property:Is facility]. If you view the pages for [MediaWiki:Smw_allows_list_Domains] and [MediaWiki:Smw_allows_list_Facilities], you will see that they have the correct ordered lists. But if you view the source, you will see something like the following: