sub:assertion {
  sub:optional_multi_placeholder-test dct:description "Optional multi-placeholder test" ;
    dct:license <http://www.apache.org/licenses/LICENSE-2.0> ;
    a <https://w3id.org/kpxl/grlc/grlc-query> ;
    rdfs:label "Optional multi-placeholder test" ;
    <https://w3id.org/kpxl/grlc/endpoint> <https://w3id.org/np/l/nanopub-query-1.1/repo/meta> ;
    <https://w3id.org/kpxl/grlc/sparql> """prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#>
prefix np: <http://www.nanopub.org/nschema#>
prefix npa: <http://purl.org/nanopub/admin/>
prefix npx: <http://purl.org/nanopub/x/>
prefix xsd: <http://www.w3.org/2001/XMLSchema#>
prefix dct: <http://purl.org/dc/terms/>

select ?np ?label ?date where {
  graph npa:graph {
    values ?__type_multi_iri {}
    ?np npx:hasNanopubType ?__type_multi_iri .
    ?np npa:hasValidSignatureForPublicKeyHash ?pubkey .
    filter not exists {  ?npx npx:invalidates ?np ; npa:hasValidSignatureForPublicKeyHash ?pubkey . }
    ?np dct:created ?date .
    optional { ?np rdfs:label ?label }
  }
}
order by desc(?date)
limit 100""" .
}