facets_eval.xq

xquery version "3.1";

declare function local:get_facet ($books as element()*, $path as xs:string, $facet_type as xs:string ) as element()?
{
 <facet type="{$facet_type}">{  
  for $book in $books 
    let $fld := 
      let $vars := map{ '': document{$book} }
      let $query :=  "declare namespace tei = 'http://www.tei-c.org/ns/1.0'; " || $path
      return xquery:eval($query, $vars )
    group by $f := $fld 
    order by $f descending
    return element {$facet_type} {attribute v {$f}, attribute number {fn:count($book)} }
  }</facet>
   
};

let $csv := fetch:text("https://gist.githubusercontent.com/CliffordAnderson/5be754415308dc407fc9/raw/daa23df71ceef375b83dd5b290284f83beeb710b/books.csv")
let $books := csv:parse($csv, map { 'header': true() })/csv/record

  return (local:get_facet($books, "//Binding", "Binding" ) ) 

  
  (: return ($book) :)