Arity error in Arrow Exp

[apb2006]

" A " => normalize-space() => tokenize("[\s,]+")

Reports normalize-space#2 not found

[apb2006]

<XQuery>
 <Module>
  <MainModule>
   <Prolog>
   </Prolog>
   <QueryBody>
    <Expr>
     <ExprSingle>
      <ArrowExpr>
       <Literal>
        <StringLiteral>" A "</StringLiteral>
       </Literal>
       <WS> </WS>
       <TOKEN>=></TOKEN>
       <WS> </WS>
       <ArrowFunctionSpecifier>
        <EQName>normalize-space</EQName>
       </ArrowFunctionSpecifier>
       <ArgumentList>
        <TOKEN>(</TOKEN>
        <TOKEN>)</TOKEN>
       </ArgumentList>
       <WS> </WS>
       <TOKEN>=></TOKEN>
       <WS> </WS>
       <ArrowFunctionSpecifier>
        <EQName>tokenize</EQName>
       </ArrowFunctionSpecifier>
       <ArgumentList>
        <TOKEN>(</TOKEN>
        <Argument>
         <ExprSingle>
          <Literal>
           <StringLiteral>"[\s,]+"</StringLiteral>
          </Literal>
         </ExprSingle>
        </Argument>
        <TOKEN>)</TOKEN>
       </ArgumentList>
      </ArrowExpr>
     </ExprSingle>
    </Expr>
   </QueryBody>
  </MainModule>
 </Module>
 <EOF>
 </EOF>
</XQuery>