Reconciling various forms of string literals

The RDF Working Group resolved its ISSUE-12, which is intended to "reconcile various forms of string literals".

The group resolved to accept the proposal documented on the WG's wiki, with the modification that preferred output form (SHOULD) is "foo" and not "foo"^^xsd:string in RDF; and we recommend that SPARQL and other WGs do the same.

Discussion highlighted several possible areas of concern, which the group believes the current proposal addresses. Specifically, it was noted that:

• The forms "foo" and "foo"^^xsd:string are equivalent input syntaxes.
• The form "foo" is the preferred output syntax.
• The WG suggests retaining the term “plain literal” in documents to avoid unnecessary rework. Such plain literals would be considered semantically equivalent to xsd:string-s.

NB: This resolution makes no statement about language-tagged literals (e.g. "foo"@en).

We invite discussion regarding the ramifications of this resolution to other working groups and implementors.