python pdb automatic pretty-printing

Question

I find myself doing this in pdb quite often:

import pprint
pprint.PrettyPrinter().pprint(variable_of_interest)

Is there a better way to pretty-print variables from pdb? I'm looking for something easier to type, and ideally something that's always available in pdb so I can use it anytime I'm debugging.

score 49 · Accepted Answer · edited Jun 20 '20 at 09:12

49

In pdb documentation at the section Debugger Commands:

pp expression

Like the p command, except the value of the expression is pretty-printed using the pprint module.

edited Jun 20 '20 at 09:12

Community

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answered Aug 15 '14 at 21:37

enrico.bacis

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@nonagon welp i've been using python for years and also didn't know about `pdb`'s `pp`. – Trevor Boyd Smith Dec 17 '18 at 21:30
@TrevorBoydSmith Haha yes, after years I just thought it would be great if pprint is loaded by default, how can I do it, then stumbled upon this. – PascalVKooten May 31 '21 at 10:45

score 6 · Answer 2 · answered Sep 07 '20 at 14:25

6

Like @enrico.bacis has mentioned pp can be used for pretty printing while using pdb.

(Pdb) pp your_var

answered Sep 07 '20 at 14:25

mrprofessor

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score 3 · Answer 3 · answered May 12 '19 at 21:15

Once you are in (Pdb) shell:

(Pdb)$ import pprint

# then you can pretty print your variables.
(Pdb)$ pp( locals() )
(Pdb)$ pp(request.data)

Also, I recommend using the new pdb alternative breakpoint(), that way you don't have to import pdb package in any of your dev environment sourcecode. It's also easier to type than pdb.set_trace()

score -1 · Answer 4 · answered Jul 15 '18 at 14:54

Here is how I am doing it:

import pdb
import pprint

"""
Debugging views
pdb.set_trace()

With pretty-print
pp(my_var)
"""
def my_view(request):
    pdb.set_trace()
    # rest of view

Then in debugger:

> (Pdb) pp(my_var)

Although, I would like to know how to edit the pdb settings to change p to pp

python pdb automatic pretty-printing

4 Answers4