How are the chances that one of these
functions will be free-text search?
Most web-applications today use some kind
of free-text search; most facet browsers as well as most (all?) Semantic Web
search engines use free-text search to enable the user to specify starting
points for further navigation.
Many SPARQL stores already implement
Today, people have to use dirty hacks like FILTER regex(?label, "%word1%") to emulate free text search.
I therefore think that it would be great if
you would foster the interoperability between SPARQL stores by including
free-text search into the spec.