Sorry for the nonsense,
I did not notice I was answering to the wrong email.
Hit the reply button with the cursor one line off.
Erich Neuwirth wrote:
another thing.
when you use MakeArgs,
all the numbers that end up in the parameter string should
be wrapped in a call to the function RNumber.
RNumber makes sure the string has the correct decimal separator
in an language combination of Excel, Windows, and R.
Michael Foord wrote:
Dino Viehland wrote:
Srivatsn's blog is an important piece of the puzzle, but the more
general answer is implementing the __*__ method directly should
always work. If it doesn't then it's a bug - like where __repr__
wasn't working w/o implementing the interface until recently.
Hello Dino,
The following doesn't work for me with IronPython 2.0B3.
namespace example
{
public class Example
{
private Dictionary<string, object> store = new
Dictionary<string, object>();
public void __setattr__(string key, object value)
{
store[key] = value;
}
public object __getattr__(string key)
{
return store[key];
}
}
}
When using it:
>>> clr.AddReference('example')
>>> from example import Example
>>> e = Example()
>>> e.a = 1
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: 'Example' object has no attribute 'a'
Do you know what protocol methods actually work?
Michael
But there is a good reason to not implement the __*__ method - and
that's ensuring that your objects will work good in a multi-language
environment. What IronPython does to expose .NET objects into Python
is it maps a large number of .NET interfaces and methods into Python
methods. If you'd like to see the all of the mappings they're
contained entirely in TypeInfo.cs. So instead of implementing
__getitem__ you can implement a C# indexer, instead of
__enter__/__exit__ you can implement IDisposable - assuming you're
not doing more interesting things w/ __enter__/__exit__, etc... If
there's some mapping that you think should exist but we don't have
let us know - for example until recently we had overlooked mapping
IDisposable.
To get the best interop if there's a .NET interface or operator
method that maps onto the Python methods you should use that. That
includes the extended operators that we've defined for the DLR
default binder like GetCustomMember as Srivatsn's blog demonstrates.
Otherwise fallback to the __*_- method.
-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Michael Foord
Sent: Sunday, July 13, 2008 10:21 AM
To: Discussion of IronPython
Subject: Re: [IronPython] Using Python special methods in C#
Dan Eloff wrote:
Something I've found a little difficult in C# is python special
methods. It seems sometimes you can just declare them on the C# class,
(__repr__?) and they will work, other times you need to implement an
interface (__call__?) is there any place this is documented?
I'm a little confused about how to add special methods on C# classes.
I want to add __getattr__ to a C# class (actually a subclass of
PythonDictionary), and I have no idea how.
This example from Srivatsn shows you how:
http://blogs.msdn.com/srivatsn/archive/2008/04/12/turning-your-net-object-models-dynamic-for-ironpython.aspx
Michael
Thanks,
-Dan
_______________________________________________
Users mailing list
[email protected]
http://lists.ironpython.com/listinfo.cgi/users-ironpython.com
--
http://www.ironpythoninaction.com/
http://www.voidspace.org.uk/
http://www.trypython.org/
http://www.ironpython.info/
http://www.theotherdelia.co.uk/
http://www.resolverhacks.net/
_______________________________________________
Users mailing list
[email protected]
http://lists.ironpython.com/listinfo.cgi/users-ironpython.com
_______________________________________________
Users mailing list
[email protected]
http://lists.ironpython.com/listinfo.cgi/users-ironpython.com
--
Erich Neuwirth, University of Vienna
Faculty of Computer Science
Computer Supported Didactics Working Group
Visit our SunSITE at http://sunsite.univie.ac.at
Phone: +43-1-4277-39464 Fax: +43-1-4277-39459
_______________________________________________
Users mailing list
[email protected]
http://lists.ironpython.com/listinfo.cgi/users-ironpython.com
