It would be nice if XSpec noticed circular imports

[ndw]

I have a directory of xspec files. I wanted to wrap them all up in a single file with imports. In the course of doing so, I managed to create a circular reference. (wrapper.xspec imported wrapper.xspec).

Curiously, this didn't cause any immediate problems. But days later when I added a top-level x:param declaration, that caused the compiled stylesheet to crash ("duplicate global variable").

That took way too long to figure out! It would be nice if the import process detected circularity and through an error.

[AirQuick]

x:import is supposed to eliminate duplicates based on node identity. I tested a simple circular x:import on Oxygen debugger and Ant and they seem to work fine. But somehow the command line (xspec.bat and xspec.sh) fails to identify the duplicate...

[AirQuick]

Seems like the problem does not happen on Saxon 9.8 (.0.12, 14, 15) on my end.

[AirQuick]

the command line (xspec.bat and xspec.sh) fails to identify the duplicate.

Saxon conforms to the standard, per https://sourceforge.net/p/saxon/mailman/message/37030023/ .
So I fixed this specific problem in #990.

It would be nice if the import process detected circularity and through an error.

This issue is still opened. The specification of x:import is not very much clear. There may be valid use cases which in part take form of circular imports... I'm not sure. Anyway I think at least a warning, if not an error, should be emitted.

[ndw]

A warning is fine as far as I'm concerned. If you think there are legitimate use cases, then something should be done to eliminate the duplicate x:param elements or it won't work anyway.

[AirQuick]

Reopening for the warning/error part.