Re: [xsl] Better "Report Map" Function?

["Michael Kay mike@xxxxxxxxxxxx" <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx>]

I wonder if this is really what you want?

You haven't declared a return type for the function, so there's going to be no
conversion applied, which means it's going to output a sequence of
interspersed text and element nodes. That's probably fine if the function call
always appears within xsl:value-of, but it's not very convenient if, for
example, you want to call it as an argument of contains() or substring(). I
would have thought a function that returned a string would be more useful.

And a function that only handles map values that are maps, elements, document
nodes, single strings, single booleans, or single integers doesn't feel very
general-purpose.

But you're right that there's probably nothing off-the-shelf that gives you
exactly what you want. For many purposes (e.g. diagnostic output) the
serialize() function with method=adaptive will be adequate, but if you want
something better then you have to do it yourself.

Incidentally, sorting the keys of a map like this will fail if the keys
include non-ordered values such as QNames, of if they include a mixture of
strings and numbers. If you want to be sure the sort won't fail, convert keys
to strings before sorting.

Michael Kay
Saxonica

> On 6 Oct 2018, at 14:33, Eliot Kimber ekimber@xxxxxxxxxxxx
<xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx> wrote:
>
> I needed a way to report the contents of maps as nicely-formatted strings
using XSLT 3 and Saxon (Saxon's built-in serialization of maps did not really
satisfy me).
>
> Here's my solution:
>
>  <xsl:function name="local:report-map">
>    <xsl:param name="map" as="map(*)"/>
>    <xsl:param name="level" as="xs:integer"/>
>
>    <xsl:variable name="indent" as="xs:string?"
>      select="(for $i in 1 to $level return '  ') => string-join()"
>    />
>    <xsl:text>&#x0a;{$indent}{{</xsl:text>
>    <xsl:for-each select="map:keys($map) => sort()">
>      <xsl:variable name="key" select="."/>
>      <xsl:variable name="value" select="map:get($map, $key)"/>
>      <xsl:text>&#x0a;{$indent}  "{$key}" : </xsl:text>
>      <xsl:choose>
>        <xsl:when test="$value instance of map(*)">
>          <xsl:text> Map:</xsl:text>
>          <xsl:sequence select="local:report-map($value, $level + 3)"/>
>        </xsl:when>
>        <xsl:when test="$value instance of element()">
>          <xsl:sequence select="$value"/>
>        </xsl:when>
>        <xsl:when test="$value instance of document-node()">
>          <xsl:text> document-node(): {name($value/*)} -
"{document-uri($value)}"</xsl:text>
>        </xsl:when>
>        <xsl:when test="$value instance of xs:string or $value instance of
xs:boolean or $value instance of xs:integer">
>          <xsl:text>"{$value}"</xsl:text>
>        </xsl:when>
>        <xsl:otherwise>
>          <xsl:text>unhandled value</xsl:text>
>        </xsl:otherwise>
>      </xsl:choose>
>    </xsl:for-each>
>    <xsl:text>&#x0a;{$indent}}}</xsl:text>
>  </xsl:function>
>
> Which produces output like this:
>
> {
>   "baseType" : "map"
>   "doc" :  document-node(): map -
"file:/Users/ekimber/workspace/paccar/repo/paccar/sample_data/test-project/ca
libration-data/MX11_NA/calibrationSLMP_MX11_NA.ditamap"
>   "engineFamilies" : "10.8M01"
>   "key" : ""
>   "relpath" : "calibration-data/MX11_NA/calibrationSLMP_MX11_NA.ditamap"
>   "type" : "map"
> }
>
> I'm happy with the result but wondering if there's not a more
efficient/cleaner/more elegant way to do the same thing?
>
> Cheers,
>
> E.
> --
> Eliot Kimber
> http://contrext.com