Oh, one possible work around is to write a C# stub that will do the begin invoke for you. That'll be annoying if you have lots of delegate types that you need to begin invoke on though.
> -----Original Message----- > From: users-boun...@lists.ironpython.com [mailto:users- > boun...@lists.ironpython.com] On Behalf Of Dino Viehland > Sent: Monday, May 04, 2009 3:18 PM > To: Discussion of IronPython > Subject: Re: [IronPython] Making asynchronous calls in IronPython > > This is actually a CLR bug. A simple repro of the issue is below if > anyone is curious. > > The CLR team has resolved this bug as "Won't Fix" and says a workaround > is available. The > only workaround I can think of is explicitly queueing the work item to > the thread pool and > provide an object for you to get state back on. I've asked them for > more information. > > Unfortunately it means that currently this just won't work in > IronPython on MS .NET at > all today :(. > > using System; > using System.Reflection; > using System.Reflection.Emit; > using System.Globalization; > > class Test { > delegate void MyDelegate(); > > public static void Main(string[]args) { > DynamicMethod test = new DynamicMethod("Hello", > typeof(void), > new Type[]{typeof(string)}, > typeof(string).Module); > > > > MethodInfo writeString = typeof(Console).GetMethod("WriteLine", > new Type[]{typeof(string)}); > > ILGenerator il = test.GetILGenerator(256); > il.Emit(OpCodes.Ldarg_0); > il.EmitCall(OpCodes.Call, writeString, null); > il.Emit(OpCodes.Ret); > > > MyDelegate dlg = (MyDelegate) > test.CreateDelegate(typeof(MyDelegate), "Hello World!"); > dlg.BeginInvoke(new AsyncCallback(Finished), null); > Console.ReadLine(); > } > > > public static void Finished(IAsyncResult ar) { > } > } > > > > > -----Original Message----- > > From: users-boun...@lists.ironpython.com [mailto:users- > > boun...@lists.ironpython.com] On Behalf Of Schmottlach, Glenn > > Sent: Monday, May 04, 2009 2:58 PM > > To: Discussion of IronPython > > Subject: Re: [IronPython] Making asynchronous calls in IronPython > > > > Okay, call me clueless . . . > > > > This is what I have so far as an example: > > > > import clr > > clr.AddReference('IronPython') > > > > from System import * > > from System.Threading import Thread > > from IronPython.Compiler import CallTarget0 > > > > class Foo: > > def start(self): > > print 'Started.' > > Thread.Sleep(3000) > > threadId = System.Threading.Thread.CurrentThread > > return 'Exiting thread %r' % (threadId) > > > > def finish(self, r): > > print 'Finished.' > > > > > > if __name__ == '__main__': > > f = Foo() > > caller = CallTarget0(f.start) > > result = caller.BeginInvoke(None, None) > > caller.EndInvoke(result) > > > > > > Can you give me a concrete example of using CallTarget0 and > > AsyncCallback to implement this? What it does now is print: > > > > Finished. > > SystemError:Object reference not set to an instance of an object. > > > > Obviously, I'm not using AsyncCallback because it's not clear to me > > what > > I pass to the constructor and where I pass the subsequent object. > > > > If you could spare me a few moments and correct this simple sample it > > would be very grateful. > > > > Thanks . . . > > > > > > -----Original Message----- > > From: users-boun...@lists.ironpython.com > > [mailto:users-boun...@lists.ironpython.com] On Behalf Of Michael > Foord > > Sent: Monday, May 04, 2009 5:48 PM > > To: Discussion of IronPython > > Subject: Re: [IronPython] Making asynchronous calls in IronPython > > > > Schmottlach, Glenn wrote: > > > I've looked at the C# examples in MSDN but they don't appear to > lend > > > themselves (at least with my limited experience in .NET) to an easy > > > implementation in IronPython due to the dynamic nature of the type > > > system in Python. > > > > > > The example I looked at: > > > > > > http://msdn.microsoft.com/en-us/library/h80ttd5f.aspx > > > > > > > > > declares a delegate type which seems difficult to do in IronPython, > > e.g. > > > > > > C# > > > > > > public delegate bool AsyncFactorCaller ( > > > int number, > > > ref int primefactor1, > > > ref int primefactor2); > > > > > > So what's the equivalent in IronPython? > > > > > > Also, (out) parameters are passed by reference to BeginInvoke and > > > EndInvoke and it's not clear to me how to handle this in > IronPython. > > > > > > So, I suspect I'm missing something in order to get things working. > > What > > > I really need to see is a concrete IronPython example and I think > > things > > > would gel at that point. Could you offer such an example . . . > Google > > > hasn't been helpful in this respect. > > > > > > > out parameters are handled by IronPython as extra return values - you > > wrap your callback function in CallTarget0 and an AsyncCallback. > > > > I hope this helps. > > > > Michael > > > > > > > > -----Original Message----- > > > From: users-boun...@lists.ironpython.com > > > [mailto:users-boun...@lists.ironpython.com] On Behalf Of Michael > > Foord > > > Sent: Monday, May 04, 2009 4:33 PM > > > To: Discussion of IronPython > > > Subject: Re: [IronPython] Making asynchronous calls in IronPython > > > > > > Schmottlach, Glenn wrote: > > > > > >> Although I'm very comfortable with CPython, I'm new to IronPython > > and > > > > >> the .NET framework. What I am looking for is sample code that > shows > > >> how to issue an asynchronous call from IronPython using the > > >> BeginInvoke/EndInvoke mechanism of .NET. > > >> > > >> > > > > > > I can't remember the usage off the top of my head - but usage from > > > IronPython is identical to usage from C#, so an MSDN example ought > to > > > give you what you need. > > > > > > All the best, > > > > > > Michael > > > > > >> Currently, I'm playing around with GTK# and a D-Bus .NET > > >> implementation (NDesk-DBus) that only provides synchronous proxy > > >> methods for D-Bus services. I believe (please correct me if I'm > > wrong) > > >> > > > > > > > > >> that I should be able to use the BeginInvoke/EndInvoke mechanism > to > > >> issue these blocking proxy requests asynchronously and be notified > > >> (via a callback) when the method has completed. > > >> > > >> My blocking proxy calls look something like this: > > >> > > >> ret = /self/._proxy.TunerGetCurrentWaveBand(0) > > >> > > >> where 'ret' returns the current waveband (AM, FM, etc..) and are > > >> called from a button "clicked" delegate. I would rather not block > > the > > > > >> GTK# dispatch loop while waiting for the reply from the service. > Can > > >> someone offer me any advice or provide a reference to sample code > > that > > >> > > > > > > > > >> illustrates the basic concept from IronPython? > > >> > > >> > > >> > > > > > --------------------------------------------------------------------- > -- > > - > > > > > >> _______________________________________________ > > >> Users mailing list > > >> Users@lists.ironpython.com > > >> http://lists.ironpython.com/listinfo.cgi/users-ironpython.com > > >> > > >> > > > > > > > > > > > > > > > -- > > http://www.ironpythoninaction.com/ > > http://www.voidspace.org.uk/blog > > > > > > _______________________________________________ > > Users mailing list > > Users@lists.ironpython.com > > http://lists.ironpython.com/listinfo.cgi/users-ironpython.com > > > > _______________________________________________ > > Users mailing list > > Users@lists.ironpython.com > > http://lists.ironpython.com/listinfo.cgi/users-ironpython.com > _______________________________________________ > Users mailing list > Users@lists.ironpython.com > http://lists.ironpython.com/listinfo.cgi/users-ironpython.com _______________________________________________ Users mailing list Users@lists.ironpython.com http://lists.ironpython.com/listinfo.cgi/users-ironpython.com
