Kaz Kylheku wrote: > Duncan Booth wrote: >> One big problem with this is that with the decorator the function has >> a name but with a lambda you have anonymous functions so your >> tracebacks are really going to suck. > > Is this an issue with this particular design that is addressed by > other designs?
Yes. Decorators don't interfere with the name of the underlying function displayed in tracebacks. > > Are the existing one-line lambdas free from this problem? No, but since a single line lambda does virtually nothing it isn't as serious. Decorators are useful enough that in some situation you might decorate every method in a class (e.g. for a web application you might apply security settings with decorators). In that situation you have just messed up every stack frame in every traceback. > > Is there really a problem? The Python tracebacks identify every frame > by file and line number, as well as name, if one is available. Great, and I suppose that if they printed out the line numbers in binary that wouldn't make it harder to understand the traceback either. I end up reading tracebacks quite a lot, and it is the sequence of the function names which matter first, I don't usually need to go and look at the file and code lines. > > Let me make the observation that name of an inner function is, alone, > insufficient to identify that function in a debugging scenario. If you > have some inner function called I, defined within function F, you need > to know that it's the I inside F, and not some other I. > If the stack frame shows I called from F then it is usually a pretty good guess that it means the I inside F. Besides, I don't usually name all my inner functions I; I find that giving them meaningful names tends to help. -- http://mail.python.org/mailman/listinfo/python-list
