From: Michael Kay <mike@sa...>  20130206 12:56:30

I'll look into it when I have a little more time  I'm in in XQuery meetings today and tomorrow, and this one will require concentrated study! I suspect what is happening is that the function that the error message is talking about is an internally generated one. For example, Saxon generally handles function closures by creating an internal function with extra arguments representing the variables in the closure. Michael Kay Saxonica On 06/02/2013 11:37, Abel Braaksma wrote: > I've rewritten the continuationpassing style function in a slightly > more readable form, but the error is the same. The weird thing about > this is, there is no anonymous function that takes two arguments. It > is my guess that something with the closures is not going entirely the > way it should: > > <xsl:function name="f:fib"> > <xsl:param name="n" as="xs:integer" /> > <xsl:param name="countfun" as="function(*)" /> > > <xsl:sequence select=" > if ($n = 1 or $n = 2) > then $countfun($n) > else > f:fib($n  1, function($x) { > f:fib ($n  2, function($y) { > $countfun($x + $y) > }) > })" /> > </xsl:function> > > Thanks, > Abel > > > On 622013 4:14, Abel Braaksma wrote: >> When I define the following continuation version of the Fibonacci >> sequencein XSLT 3: >> >> <xsl:function name="f:fib"> >> <xsl:param name="n" as="xs:integer" /> >> <xsl:param name="countfun" as="function(*)" /> >> >> <xsl:sequence select=" >> if ($n = 1 or $n = 2) >> then $countfun(1) >> else let $first := >> function($x as xs:integer) as function(*) >> { >> let $second := function($y as xs:integer) as >> function(*) >> { >> $countfun($x + $y) >> } >> return f:fib($n  2, $second) >> } >> return f:fib($n  1, $first)" /> >> </xsl:function> >> >> and I call it as follows: >> >> <xsl:valueof select="f:fib(10, function($a as xs:integer){$a})" /> >> >> the expected result is 55. However, I receive the following error: >> >> Engine name: SaxonEE 9.4.0.4 >> Severity: fatal >> Description: Required item type of second argument of anonymous >> function is function(); supplied value has item type xs:integer >> Start location: 36:0 >> URL: http://www.w3.org/TR/xslt20/#errXTTE0790 >> >> The function is inspired by this snippet http://fssnip.net/eU, though >> other functional languages have similar examples. The idea behind the >> excercise is to eliminate the double recursive exit pointof the >> function by creating a continuation function. However, either the >> error is confusing(I don't see any anonymous function call with >> afunction argument) or something else is happening. >> >> I also tried the fully typed version, and an untyped version. Here's >> the fully typed variant: >> >> <xsl:function name="f:fib" as="xs:integer"> >> <xsl:param name="n" as="xs:integer" /> >> <xsl:param name="countfun" as="function(xs:integer) as xs:integer" /> >> >> <xsl:sequence select=" >> if ($n = 1 or $n = 2) >> then $countfun(1) >> else let $first := >> function($x as xs:integer) as xs:integer >> { >> let $second := function($y as xs:integer) as >> xs:integer >> { >> $countfun($x + $y) >> } >> return f:fib($n  2, $second) >> } >> return f:fib($n  1, $first)" /> >> </xsl:function> >> >> >> Any idea what I'm missing here, or is this perhaps an error with Saxon? >> >> Thanks, >> Abel >> >> >> >> >>  >> Free NextGen Firewall Hardware Offer >> Buy your Sophos nextgen firewall before the end March 2013 >> and get the hardware for free! Learn more. >> http://p.sf.net/sfu/sophosd2dfeb >> >> >> _______________________________________________ >> saxonhelp mailing list archived athttp://saxon.markmail.org/ >> saxonhelp@... >> https://lists.sourceforge.net/lists/listinfo/saxonhelp > > > >  > Free NextGen Firewall Hardware Offer > Buy your Sophos nextgen firewall before the end March 2013 > and get the hardware for free! Learn more. > http://p.sf.net/sfu/sophosd2dfeb > > > _______________________________________________ > saxonhelp mailing list archived at http://saxon.markmail.org/ > saxonhelp@... > https://lists.sourceforge.net/lists/listinfo/saxonhelp 