I'm new to the list, so give me some time to grok why "new statement/keyword" is a Bad Idea. I'll refrain from the usual, "It's just a new statement, what's so bad about that" so you guys don't have to scold me. I suspect the reason relates to bloating the core language :D
I think the in statement already hooks into __contains__. So I don't think using "foo is in bar" would work. That already exists and means something else.
I forgot about the try / catch approach. I will use this, as I think it's more Pythonic?
As far as using class, from, or with; overloading existing keywords seems a bit dangerous.
At this point and the more I think about it, I feel pretty convinced it's a bad idea.
On Apr 1, 2010, at 1:54 PM, Bruce Leban wrote:
I think this is a great idea, but I would not want to introduce a new keyword. How about
foo is in bar = hasattr(foo,bar) foo is not in bar = not hasattr(foo,bar)
But there are other common checks I do all the time that I would really like to have shortcuts for. Here are ways to do them without new keywords:
foo is class bar = isinstance(foo,bar) foo is from bar = issubclass(foo,bar) foo is with bar = type(foo) == type(bar)
Can we make an exception to the moratorium, just for today?
--- Bruce http://www.vroospeak.com
On Thu, Apr 1, 2010 at 8:15 AM, Robert Madole email@example.com wrote: So I just wrote my 1-gazillionth "if hasattr('method', my_object):" and wanted badly to write this.
if 'method' on my_object:
I'm not the most experienced Python user, but as far as I can tell hasattr is the preferred way of checking if a method exists.
Please correct me if there is a better way, otherwise I'd like to see what everyone thinks about an "on" statement being added to the Python language.
Rob Madole _______________________________________________ Python-ideas mailing list Pythonfirstname.lastname@example.org http://mail.python.org/mailman/listinfo/python-ideas