Oh boy! XSpec v3.0 is scheduled for April this year, including (among other things) SchXslt 1.9.5 as replacement for the skeleton implementation. I'm at the ready to fix the issues that will be detected this way.
The next version of SchXslt2 will support a processing instruction schxslt.declare-param to aid writing ISO Schematron w/ abstract patterns. I chose a processing instruction over reusing the sch:param element to not interfere with the current standardisation process.
If the processing instruction is used, the transpiler terminates with an error if a declared parameter is not provided, and if a provided parameter ist not declared.
https://git.sr.ht/~dmaus/schxslt2/tree/main/item/src/main/resources/content/transpile.xsl#L186
Today I Learned: The xsl:import element children must precede all other element children of an xsl:stylesheet element, including any xsl:include element children and any user-defined data elements.
