> Inheriting from SyntaxError doesn't work! When I create a new exception, I > generally subclass from the built-in exception it most resembles, in case > there was some reason to also catch it via an ancestor. But I'm not sure if > that is really all that useful an idea in practice. How do you folk do it?
If somebody wanted to catch a ValueError, would they also mean to catch my error? (The same with SyntaxError and so on). Probably not. If they would, then I raise the relevant exception. It is very possible to accidentally catch the wrong thing if you put too much in a try block, and I don't like making that any easier. -- Devin On Fri, Jan 6, 2012 at 10:24 PM, Chris Fuller <cfuller...@thinkingplanet.net> wrote: > I had an interesting experience today. > > Python 2.7.1 (r271:86832, Nov 28 2010, 19:31:37) > [GCC 4.4.5] on linux2 > Type "help", "copyright", "credits" or "license" for more information. >>>> class Foo(Exception): > ... def __init__(self, a,b,c): > ... self.args = (a,b,c) > ... >>>> raise Foo(1,2,3) > Traceback (most recent call last): > File "<stdin>", line 1, in <module> > __main__.Foo: (1, 2, 3) >>>> class Foo(SyntaxError): > ... def __init__(self, a,b,c): > ... self.args = (a,b,c) > ... >>>> raise Foo(1,2,3) > Traceback (most recent call last): > File "<stdin>", line 1, in <module> > __main__.Foo: None > > > Inheriting from SyntaxError doesn't work! When I create a new exception, I > generally subclass from the built-in exception it most resembles, in case > there was some reason to also catch it via an ancestor. But I'm not sure if > that is really all that useful an idea in practice. How do you folk do it? > > By the way, inheriting from StandardError, the direct ancestor of > SyntaxError, works as expected, and its parent is Exception. > > Cheers > _______________________________________________ > Tutor maillist - Tutor@python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
