Saxon

I was trying to use http://saxonica.com/html/documentation/extensions/attributes/capture.html and I have found an inconsistency between a normal accumulator "capturing" nodes

	<xsl:accumulator name="items" as="element(item)*" initial-value="()">
		<xsl:accumulator-rule phase="end" match="item" select="$value, ."/>
	</xsl:accumulator>

where the use of

	<xsl:template match="item">
		<xsl:next-match/>
		<xsl:message>item: {string(@id)}, count(accumulator-after("items")): {count(accumulator-after('items'))}, accumulator-after("items")!@id!string(): {accumulator-after("items")!@id!string()}</xsl:message>
	</xsl:template>

indicates that accumulator-after("items") includes the currently matched item (e.g. output is

item: i2, count(accumulator-after("items")): 2, accumulator-after("items")!@id!string(): i1 i2

) and a streaming, capturing accumulator

	<xsl:accumulator name="items" as="element(item)*" initial-value="()" streamable="yes">
		<xsl:accumulator-rule phase="end" match="item" select="$value, ." saxon:capture="yes"/>
	</xsl:accumulator>

where the accumulator-after("items") doesn't seem to include the currently matched item (e.g. output is alike

item: i2, count(accumulator-after("items")): 1, accumulator-after("items")!@id!string(): i1

), it only includes items preceding the currently matched one.

Tested with Saxon-EE 9.9.0.1J.

Is that difference intentional?

The other oddity is that even without the saxon:capture the code runs with streaming (I would have thought that the select="$value, ." is not motionless)

Processing file:/C:/SomePath/input-3-items.xml
Streaming file:/C:/SomePath/input-3-items.xml
Using parser com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser
item: i1, count(accumulator-after("items")): 0, accumulator-after("items")!@id!string():
item: i2, count(accumulator-after("items")): 1, accumulator-after("items")!@id!string(): i1
item: i3, count(accumulator-after("items")): 2, accumulator-after("items")!@id!string(): i1 i2
<?xml version="1.0" encoding="UTF-8"?><items>
        <item id="i1">value 1</item>
        <item id="i2">value 2</item>
        <item id="i3">value 3</item>
</items>

So I am confused, why can the streaming code capture a complete element node without using saxon:capture and why is there the difference between a streaming and not streaming as to whether the currently matched node is included in the accumulator-after result?