Help:Special property Allows value

The Allows value property is a special property in Semantic MediaWiki with a built-in meaning: it lists one permissible value for a property.

You can use this special property with a property of any datatype to limit its possible values. It is similar in its functionality to.

When  is used to set a property to a value that is not allowed, the property will not be set, and a warning sign will be shown. When using  to set the property, the error will be silently ignored. To find all pages that use a value that is not allowed, can be used.

See the property page "Allows value" to see which pages use this special property on this wiki.

Simple
For example, the page for a "Problem severity" property might contain: Allows value::Trivial Allows value::Minor Allows value::Normal Allows value::Major Allows value::Critical

Ordered
Enumerating several allowed values does not put the possible values of a property in that order. Properties will always sort in the natural order provided by the datatype assigned to them. You can ensure that alphabetical sort order is appropriate for properties of e.g. by using a prefix, for example: Allows value::a - Trivial Allows value::b - Minor Allows value::c - Normal Allows value::d - Major Allows value::e - Critical ... Thus you can query for greater-than-or-equal or less-than-or-equal values, for example

Bounded intervals and ranges
Starting with bounded intervals can be specified for values to properties of  and .CiteRef::gh:smw:3292

A range can be defined using  and  :
 * or in combination
 * or in combination

An interval can be defined using the bounded range  indicator: