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pythondebuggingipythonbreakpoints

Debug Python Script Using Multiple Breakpoints in IPython

How do we set multiple breakpoints in Python using IPython, so that for example we stop at line 4 and line 100?

Also, can we change our mind and set extra breakpoints while already in debugging?

Solution

  • iPython provides IPython.core.debugger.Tracer debugger class which can be used to debugging.

    Let's say I have below code written in myScript.py:

    from IPython.core.debugger import Tracer
zz = Tracer()

print "iPython"
zz()
print "is a"
print "command shell"
zz()
print "for"
print "interactive computing"
print "in"
print "multiple programming languages"
print "including"
print "Python"

    As you can see I have set 2 breakpoints in the script from the beginning at Line 5 and 8. Below, I am running this script and will be setting 2 more breakpoints at line 12 & 13.

    $ ipython myScript.py
iPython
> /home/user/Documents/myScript.py(6)<module>()
      4 print "iPython"
      5 zz()
----> 6 print "is a"
      7 print "command shell"
      8 zz()

ipdb> break 12
Breakpoint 1 at /home/user/Documents/myScript.py:12
ipdb> break 13
Breakpoint 2 at /home/user/Documents/myScript.py:13

    Also, when inside debugging, you can use commands c for continue and n for next step. Hopefully, it helps you.