Tracing Function Execution
You can trace the arguments supplied, to and the result values produced by functions using C-c M-t v. CIDER will prompt you for the name of the function you want to trace, defaulting to the previous top-level definition.
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Invoking C-c M-t v again for the same function will result in the function being untraced.
You can also use C-c M-t n to toggle tracing on and off for an entire namespace.