Diagnostics and tests
Warnings, tracing, and test helpers.
Orientation
Diagnostics turn warnings, stops, traces, and tests into structured values. Start with small test cases before adding tracing to a larger calculation.
Start with a small diagnostic so you can see its result before adding tracing to a larger program.
A worked example
The final line is the displayed value; the earlier lines set up the experiment. Keep the setup visible so you can tell whether a name, a cell, or a collection is being reused when the expression changes.
Read the result
Some diagnostic capabilities are best viewed in a script or CLI host; RatCalc keeps their invocation explicit.
Change the diagnostic message and compare its displayed value with an ordinary calculation.
Keep going
Continue with Verified rule for a task that uses diagnostic helpers.