This package provides an interface to Saxon tracing and debugging capabilities.

The package was originally created by Edwin Glaser.

The package includes three tracing modules that can be optionally selected: `XSLTTraceListener`, `XQueryTraceListener`, and `TimedTraceListener`. These all receive notification of the same events, but select and format the events in different ways to meet different requirements. Other events are notified through the `TraceListener` interface that are ignored by tracing applications, but may be of interest to debuggers.