Default values of function parameters

It is not possible to set a function parameter to a default value. See the following example for a correct way how to achieve this functionality.

XSLT

      <xsl:stylesheet
                  xmlns:my="myFunctions"
                  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
                  version="2.0"
                  exclude-result-prefixes="my">
            <xsl:output  method="xml"
                        indent="yes"
                        omit-xml-declaration="yes"/>

            <xsl:function  name="my:multiply">
                  <xsl:param  name="a"/>
                  <xsl:param  name="b"
                              select="1"/>
                  <xsl:value-of  select="$a * $b"/>
            </xsl:function>

            <xsl:template  match="/aaa">
                  <xsl:value-of  select="my:multiply(4)"/>
            </xsl:template>

      </xsl:stylesheet>

XML

<aaa/>

Output

Error:

error - XTSE0760
Function parameters cannot have a default value

error - XPST0003
XPath syntax error at char C on line L in {my:multiply(4)}: Cannot find a matching 1-argument function named {myFunctions}multiply()

Failed to compile stylesheet. 2 errors detected.

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