Change Details

We might want to consider a constraint on the entity type of a statement’s subject. - We currently have no way to express the constraint “only properties should have //property constraint// statements”, which has already resulted in some misuse of the property: [example 1](https://www.wikidata.org/w/index.php?title=Q1667500&oldid=478113631#P2302), [example 2](https://www.wikidata.org/w/index.php?title=Q21126229&oldid=477738338#P2302). - This would probably also be useful in connection with structured data on commons – there might be some properties that we only want on mediainfo entities (not sure), but much more importantly there are lots of properties that we //don’t// want on mediainfo entities (only on items).

Some properties are supposed to be used only on one or a few entity types. As an editor I want to be able to define which entity types a property can be used on so I can easily find cases where the property is used in a wrong context via the existing constraint system. Violation message shown to the user on violating statements: "Entity type constraint: This property should only be used on "$entitytype"." Constraint statement on the property: "property constraint" -> "entity type constraint" with qualifier "TODO" Examples where this is likely to be used: * indicating that "property constraint" should only be used on properties * restricting "rhymes with" and similar properties to Lexemes

We might want to consider a constraint on the entity type of a statement’s subjectSome properties are supposed to be used only on one or a few entity types. As an editor I want to be able to define which entity types a property can be used on so I can easily find cases where the property is used in a wrong context via the existing constraint system. - We currently have no way to express the constraint “only properties should have //property constraint// statements”, which has already resulted in some misuse of the property: [example 1](https://www.wikidata.org/w/index.php?title=Q1667500&oldid=478113631#P2302), [example 2](https://www.wikidata.org/w/index.php?title=Q21126229&oldid=477738338#P2302).Violation message shown to the user on violating statements: "Entity type constraint: This property should only be used on "$entitytype"." - This would probably also be useful in connection with structured data on commons – there might be some properties that we only want on mediainfo entities (not sure), but much more importantly there are lots of properties that we //don’t// want on mediainfo entities (only on items).Constraint statement on the property: "property constraint" -> "entity type constraint" with qualifier "TODO" Examples where this is likely to be used: * indicating that "property constraint" should only be used on properties * restricting "rhymes with" and similar properties to Lexemes