Re: How to write (existential) predicates with maps/Wh

I'm having trouble understanding/reproducing this. Can you supply a complete repro? (I.e., the source data that results in this error)

{
    "locations" : [
      {
          "id" : "i1",
          "types" : [
              {
                "name" : "foo"
              },
              {
                "name" : "bar"
              }
          ]
      },
      {
          "id" : "i2",
          "types" : [
              {
                "name" : "baz"
              }
          ]
      },
      {
          "id" : "i3",
          "types" : [
              {
                "name" : "foo"
              },
              {
                "name" : "baz"
              }
          ]
      }
    ]
}

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
	xmlns:xs="http://www.w3.org/2001/XMLSchema"
	exclude-result-prefixes="#all"
	version="3.0">

  <xsl:param name="json" as="xs:string">
{
    "locations" : [
      {
          "id" : "i1",
          "types" : [
              {
                "name" : "foo"
              },
              {
                "name" : "bar"
              }
          ]
      },
      {
          "id" : "i2",
          "types" : [
              {
                "name" : "baz"
              }
          ]
      },
      {
          "id" : "i3",
          "types" : [
              {
                "name" : "foo"
              },
              {
                "name" : "baz"
              }
          ]
      }
    ]
}
  </xsl:param>

On 11 Feb 2019, at 12:09, Martin Honnen martin.honnen@xxxxxx <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx> wrote:

When using XPath 3.1 (e.g. in XSLT 3) on maps I have found that I have to change my coding habit a bit when writing predicates that want to check the existence of some nested map, while I hoped to be able to write e.g.

?locations?*[?types?*[?name = 'foo']]

to select all (map) members of the "locations" array that have a "types" array with at least one (map) member having a property "name" with value "foo" I get an error

Effective boolean value is not defined for sequence starting with an atomic value other than a boolean, number, or string


So in contrast to my experience with writing predicates on XML it seems for maps I have to explicitly use the "exists" function e.g.

?locations?*[exists(?types?*[?name = 'foo'])]

or a "some .. in" expression

?locations?*[some $m in ?types?* satisfies $m?name = 'foo']


Is there any more compact way to write such a check?

What is the reason that the effective boolean value was not extended to give true for a sequence with a map?