On Mar 17, 1:54 pm, Stargaming <[EMAIL PROTECTED]> wrote: > On Sun, 16 Mar 2008 20:54:01 -0700, WaterWalk wrote: > > Hello. I wonder what's the effective way of figuring out how a piece of > > python code works. > > If your Python code is well-written, it should be easy figuring out what > it means by just reading it. For more complex programs, of course, this > method can fail. > > > With C I often find it very useful to be able to run > > the code in step mode and set breakpoints in a debugger so I can watch > > how the it executes, how the data change and how the code jumps from one > > function to another. But with Python, the debugger is a little > > primitive. The default IDLE doesn't even allow me to set a breakpoint. > > When the code is long, I am often lost in it. > > IDLE is just, well, a batteries-included editor. There are many people > (me included) who do *not* like it because it's so weak and doesn't have > any real uses cases if your programs get sufficiently complex (because > IDLE itself is sufficiently primitive). > > You might be interested in *real* debuggers, such as the Python Debugger > `PDB <http://docs.python.org/lib/module-pdb.html>`_. If you don't find > its usage obvious, a quick google search just turned up a nice `tutorial > <http://www.ferg.org/papers/debugging_in_python.html>`_. > > You might find the `Python Profilers <http://docs.python.org/lib/ > profile.html>`_ particularly interesting, `profile` for finding out which > function sucks up the most calls/time, `trace` for more sophisticated > stuff. > `pythontracer <http://code.google.com/p/pythontracer/>` sounds like a > good combination of both. > > > So I'm curious how to read code effectively. I agree that python code is > > clear, but when it becomes long, reading it can still be a hard work. > > A common practice is just inserting `print` statements since it's so > easy. If you think your debugging isn't temporary but could be useful and > will be enabled every now and then, you could also use the `logging > module <http://docs.python.org/lib/module-logging.html>`_ with the > ``DEBUG`` level. > > There was a blog post recently about how to do this `generically for > functions <http://wordaligned.org/articles/echo>`_. > > > BTW. I think this problem also exists in other script languages. > > FWIW, I think it's particularly easier in scripting languages to > implement all kinds of tracing (apart from debugging, which is rather > unpopular in Python) because you have one *extra* level (the interpreter) > between your machine and your code. > > HTH, > Stargaming
Thanks for your informative reply. I'll try them. I think I need more practice to familiarize myself with those idioms of Python. -- http://mail.python.org/mailman/listinfo/python-list
