Given this XML data:

```

<root>
  <item>apple</item>
  <item>orange</item>
  <item>banana</item>
</root>

```

I can use this XSLT markup:

```

...
<xsl:for-each select="root/item">
  <xsl:value-of select="."/>,
</xsl:for-each>
...

```

to get this result:

> 
>  apple, orange, banana,
> 

but how do I produce a list where the last comma is not present? I assume it can be done doing something along the lines of:

```

...
<xsl:for-each select="root/item">
  <xsl:value-of select="."/>
  <xsl:if test="...">,</xsl:if>
</xsl:for-each>
...

```

but what should the test expression be? 

I need some way to figure out how long the list is and where I currently am in the list, or, alternatively, if I am currently processing the last element in the list (which means I don't care how long it is or what the current position is).