How to construct triples manually in Marklogic - xquery

Question

I have been trying to insert triples in Marklogic using this query
xquery version "1.0-ml";
import module namespace sem = "http://marklogic.com/semantics"
at "/MarkLogic/semantics.xqy";
declare variable $TRIPLE as xs:string external ;
declare variable $GRAPHNAME as xs:string external ;
let $TRIPLE:="sem:triple(sem:iri('http://smartlogic.com/document#testForTriples.xml'),sem:iri('http://www.smartlogic.com/schemas/docinfo.rdf#type'),'document')"
let $GRAPHNAME :="sem:iri('testGraph')"
let $r :=
sem:graph-insert($GRAPHNAME, $TRIPLE)
return <result>{$r}</result>
Unfortunately, that returns a coercion error:
XDMP-AS: (err:XPTY0004) $graphname as sem:iri -- Invalid coercion: "sem:iri('testGraph')" as sem:iri
What am I doing wrong?

Answer 1

You should not put quotes around sem:triple and sem:iri, they are type cast functions:
xquery version "1.0-ml";
import module namespace sem = "http://marklogic.com/semantics"
at "/MarkLogic/semantics.xqy";
let $TRIPLE := sem:triple(sem:iri('http://smartlogic.com/document#testForTriples.xml'),sem:iri('http://www.smartlogic.com/schemas/docinfo.rdf#type'),'document')
let $GRAPHNAME := sem:iri('testGraph')
let $r := sem:graph-insert($GRAPHNAME, $TRIPLE)
return <result>{$r}</result>
If you are trying to create the triples dynamically, pass through a sem:triple or sem:iri objects from external, or pass through the string values, and cast them inside the code.
HTH!