<?xml version="1.0" encoding="UTF-8" ?>
<root>
	<item no="0" name="0name"/>
	<item no="1" name="1name"/>
	<item no="2" name="2name"/>
</root>

<?xml version="1.0" encoding="UTF-8" ?>
<spr>
	<s id="0" name="first"/>
	<s id="1" name="second"/>
</spr>

<?xml version='1.0' encoding='UTF-8' ?>
<id_spr no="0" name="0name" sprname="first"/>
<id_spr no="1" name="1name" sprname="second"/>
<id_spr no="2" name="2name" sprname=""/>

<?xml version="1.0"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
	<xsl:output method="xml" indent="yes" encoding="UTF-8"/>
	<xsl:variable name="sprs" select="document('spr.xml')"/>
	<xsl:template match="/">
		<xsl:for-each select="root/item">
			<id_spr>
				<xsl:variable name="spr" select="$sprs/spr/s[@id=@no]"/>
                                <!-- spr - почему-то пустая! -->
				<xsl:attribute name="no">
					<xsl:value-of select="@no"/>
				</xsl:attribute>
				<xsl:attribute name="name">
					<xsl:value-of select="@name"/>
				</xsl:attribute>
				<xsl:attribute name="sprname">
					<xsl:value-of select="$spr/@name"/>
				</xsl:attribute>
			</id_spr>
		</xsl:for-each>
	</xsl:template>
</xsl:stylesheet>

<xsl:variable name="spr" select="$sprs/spr/s[@id=current()/@no]"/>