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      <h1>Streaming</h1>
      <p>The <code>saxon:iterate</code> instruction and its subsidiary instructions <code>saxon:break</code>, <code>saxon:continue</code>,
and <code>saxon:finally</code> are now available only in Saxon-EE. This reflects the fact that the instructions are designed 
 primarily for use with streaming, which is available only in Saxon-EE.</p>
      <p>The behaviour of <code>saxon:iterate</code> has been changed in the case where a <code>saxon:continue</code> instruction
does not specify values for all the parameters declared on the containing <code>saxon:iterate</code> instruction. Any parameters
for which no value is supplied now retain their previous value (that is, the effect is the same as specifying <code>&lt;xsl:with-param name="p" select="$p"/&gt;</code>).
Previously such parameters reverted to their default value. A further change is that it is no longer possible to specify <code>required="yes"</code> on
<code>saxon:iterate</code> parameters. These changes are in line with the (as-yet-unpublished) XSLT 2.1 draft specification.</p>
      <p>Saxon 9.2 introduces the concept of <i>streaming templates</i>. This allows hierarchic processing of a document using
<code>&lt;xsl:apply-templates&gt;</code> to operate in a streaming pass over the document, without building the tree in memory.
The templates, of course, have to conform to strict rules to make them streamable. Nevertheless a great many simple transformations
can be implemented this way: for example, renaming elements, deleting selected elements, computing new attribute values,
and so on.</p>
      <p>For more details see <a class="bodylink" href="../../sourcedocs/streaming/streaming-templates.xml">Streaming Templates</a>.</p>
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