10. Debugging code¶
Debugging code is always a very important part of the development process. In this section, we shall try to give a quick look on how to do it.
To debug code once an exception is raised, you can call:
You can also toggle automatic postmorten debug with:
Or by starting ipython with the
--pdb option (i.e.
ipython --pdb). This way whenever an exception is raised the debugger will be started automatically.
10.2. Easy breakpoint¶
To start the debugger at an specific point in a Python code, you can insert the following inside (a function, for example):
import ipdb ipdb.set_trace()
def func(x): y = x**2 import ipdb ipdb.set_trace() return y
10.3. Start debugging on the current terminal¶
You can also start debugging on the current terminal by using:
import ipdb ipdb.set_trace("", locals(), globals())
10.4. Debugger commands¶
There are many command you can run inside a debugger, other than just python code, the most important being:
d(own): d or down go down in the context.
u(p): u or up go up in the context.
s(tep): executes the current line and stops, but if the line is itself another function, the it go inside it.
n(ext)on the other hand always goes to the next line.
l(ist): show more code around.
p: in general just typing a variable will allow you to see its content, but what if a variable has the same name of a command, then just append p before it, example: