Advanced debugging—tracing

Tracing of a program right from the beginning can often be used as an advanced debugging technique. Tracing allows a developer to trace program execution, find caller/callee relationships, and figure out all functions executed during the run of a program.

The trace module

Python comes with a default trace module as part of its standard library.

The trace module takes one of the –trace, --count, or –listfuncs options. |The first option traces and prints all the source lines as they are executed. The second option produces an annotated list of files, which shows how many times a statement was executed. The latter simply displays all the functions executed by running of the program.

The following is a screenshot of the subarray problem being invoked by the –trace option of the trace module:

Tracing program execution using the trace module by using its –trace option.

As you can see, the trace module, traced the entire program execution, printing the lines of code one by...