[XSLT 2] base-uri of input's dir

<xsl:template match="textdata[@fileref]">
  <xsl:variable name="dir_abs"
    select="replace(base-uri(/),'[^\/]+$','')"/>
  <!--
  AFAICS, basically resolve-uri()
  concatenates if @fileref is relative, and
  leaves unchanged if it's absolute
  -->
  <xsl:variable name="file_abs"
    select="resolve-uri(@fileref,$dir_abs)"/>
  <xsl:copy-of select="unparsed-text($file_abs,'utf-8')"/>
</xsl:template>

<xsl:template match="textobject[textdata[@fileref]]">
  <xsl:apply-templates/>
</xsl:template>

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