No port attribute allowed on p:with-input of p:if?

I have tried to run some XProc 3 code doing

   <p:if test="$some-variable">
     <p:with-input port="source" pipe="foo@bar"/>

Morgana XProc (tested with MorganaXProc-IIIse 0.9.2.6-beta) then tells me

Error XS0010 in ...: Attribute 'port' not allowed on p:with-input as
child of p:if.

That left me puzzled and I tried to find it outlined in
https://spec.xproc.org/master/head/xproc/#p.if but I can't.

Erik's book tells me "Do not use a name attribute (the input port is
anonymous).".

I supposed that is meant to tell me "Do not use a port attribute".

So I get my code to run by omitting the "port" attribute with e.g.

   <p:if test="$some-variable">
     <p:with-input pipe="foo@bar"/>


Shouldn't the spec somehow state that the "port" attribute on
"p:with-input" of a "p:if" is not allowed or define that the input port
is anonymous?

Received on Friday, 8 May 2020 18:01:52 UTC