Re: Stylesheet parameters and packages?

Is there a rule of thumb for managing stylesheet parameters when using
a package hierarchy, that is, in situations where packages use other
packages? I would like to set a $debug parameter in all packages, both
the lowest-level collections of user-defined functions and the
higher-level packages that import those libraries, and that are then
imported, themselves, by other stylesheets. But as I fiddle with the
options, either I am notified by the mid-level package that a
parameter has not been declared there (even though it is declared in a
lower-level package that I am using in the mid-level one, and the XSLT
3.0 spec tells me that stylesheet parameters are obligatorily public)
or, when I declare the parameter in the mid-level package, that it
conflicts with the lower-level declaration. In case this is helpful,
the point of the $debug parameter is that I want to write diagnostic
messages to stderr using <xsl:message> B when the $debug parameter
value is true, and I need to be able to generate messages of this sort
from both the low-level and mid-level packages.

Is that XSLT 3 packages? It might help if you show minimal examples
generating those problems, together with an explanation of the XSLT 3
processor you use.

The simplest samples I could come up with a three packages package1.xsl,
package2.xsl, package3.xsl

<xsl:package
B B B  name="http://example.com/mp/p1"
B B B  package-version="1.0"
B B B  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
B B B  xmlns:xs="http://www.w3.org/2001/XMLSchema"
B B B  exclude-result-prefixes="#all"
B B B  version="3.0">

<xsl:package
B B B  name="http://example.com/mp/p2"
B B B  package-version="1.0"
B B B  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
B B B  xmlns:xs="http://www.w3.org/2001/XMLSchema"
B B B  exclude-result-prefixes="#all"
B B B  version="3.0">

B B B  <xsl:template name="xsl:initial-template" visibility="public">
B B B B B B B  <xsl:value-of select="$debug"/>
B B B  </xsl:template>

<?xml version="1.0" encoding="UTF-8"?>
<xsl:package
B B B  name="http://example.com/mp/p3"
B B B  package-version="1.0"
B B B  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
B B B  xmlns:xs="http://www.w3.org/2001/XMLSchema"
B B B  exclude-result-prefixes="#all"
B B B  version="3.0">

B B B  <xsl:use-package name="http://example.com/mp/p2" version="1.0">
B B B B B B B  <xsl:accept component="template" names="*"
visibility="public"/>
B B B  </xsl:use-package>

I can run both package2.xsl or package3.xsl with Saxon 10 from the
command line and the value of the parameter declared in package1.xsl is
output. I have to use the option lib:package1.xsl when running
package2.xsl and the option lib:"package1.xsl;package2.xsl" when running
package3.xsl. For simplicity I have also not used an input document but
used the option -it to run that template named xsl:initial-template in
package2.xsl.