Unions of sequences

• union or |

• Duplicates are eliminated

<?xml version="1.0"?> 
<xsl:stylesheet version="2.0" 
                xmlns:xsl="http://www.w3.org/1999/XSL/Transform">

  <xsl:output indent="yes"/>             
                
  <xsl:template match="/">
    <numbers>
      <xsl:for-each select='(3 to 10) | (5 to 12) | (20 to 23)'>
        <integer>
          <xsl:value-of select="."/>
        </integer>
      </xsl:for-each>
    </numbers>
  </xsl:template>

</xsl:stylesheet>

Output:

<numbers>
<integer>3</integer>
<integer>4</integer>
<integer>5</integer>
<integer>6</integer>
<integer>7</integer>
<integer>8</integer>
<integer>9</integer>
<integer>10</integer>
<integer>11</integer>
<integer>12</integer>
<integer>20</integer>
<integer>21</integer>
<integer>22</integer>
<integer>23</integer>
</numbers>