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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='color:#1F497D'>By the way, I fixed this by just overloading the “+” operator the normal way C# operators are overloaded, had it accept “object” on the right-hand-side so Python functions would make their way into it, and then used ObjectOperations.ConvertTo to convert the Python function to a System.EventHandler.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0in 0in 0in 4.0pt'><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Jimmy Schementi <br><b>Sent:</b> Tuesday, February 16, 2010 12:09 AM<br><b>To:</b> Discussion of IronPython<br><b>Subject:</b> RE: Monkey-patching CLR types<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoPlainText><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>Dino Viehland wrote:<o:p></o:p></span></p><p class=MsoPlainText><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>> If you strongly type handler to a delegate type IronPython should convert the<o:p></o:p></span></p><p class=MsoPlainText><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>> function to the delegate type on the call.<o:p></o:p></span></p><p class=MsoPlainText><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'><o:p> </o:p></span></p><p class=MsoPlainText><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'>Unfortunately it doesn't seem to </span><span style='font-size:11.0pt;font-family:Wingdings;color:black'>L</span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'>. I repro'd that it doesn't on the desktop as well as in Silverlight; here’s a desktop repro:<o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'>>>> import clr<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'>>>> clr.AddReferenceToFile("pyext")<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'>>>> import pyext<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'>>>> t = pyext.TestClass()<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'>>>> def foo(s, e): pass<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'>...<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'>>>> import System<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'>>>> t.AttachEvent("foo", System.EventHandler(foo))<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'>foo hooked!<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black;background:yellow;mso-highlight:yellow'>>>> t.foo += foo<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black;background:yellow;mso-highlight:yellow'>Traceback (most recent call last):<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black;background:yellow;mso-highlight:yellow'> File "<stdin>", line unknown, in <module><o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black;background:yellow;mso-highlight:yellow'>TypeError: unsupported operand type(s) for +=: 'MyEvent' and 'function'</span><span style='color:black'><o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'>Also, when using a EventHandler as the right-hand-side of the +=, the AttachEvent method gets called, but still complains that the “foo” attribute doesn’t exist:<o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black;background:yellow;mso-highlight:yellow'>>>> t.foo += System.EventHandler(foo)<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black;background:yellow;mso-highlight:yellow'>foo hooked!<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black;background:yellow;mso-highlight:yellow'>Traceback (most recent call last):<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black;background:yellow;mso-highlight:yellow'> File "<stdin>", line unknown, in <module><o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black;background:yellow;mso-highlight:yellow'>AttributeError: 'TestClass' object has no attribute 'foo'</span><span style='color:black'><o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'>Any ideas? Here’s the pyext.cs stub that I used:<o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'>//<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'>// pyext.cs<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'>//<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'>using Microsoft.Scripting.Runtime;<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'>using System;<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'>using Microsoft.Scripting.Utils;<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'>using System.Runtime.CompilerServices;<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'>[assembly: ExtensionType(typeof(pyext.TestClass), typeof(pyext.TestClassExtension))]<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'>namespace pyext {<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> public class TestClass {<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> public void AttachEvent(string eventName, EventHandler handler) {<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> Console.WriteLine(string.Format("{0} hooked!", eventName));<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> }<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> }<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> public static class TestClassExtension {<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> [System.Runtime.CompilerServices.SpecialNameAttribute]<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> public static object GetBoundMember(TestClass obj, string name) {<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> return new MyEvent(obj, name);<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> }<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> }<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> public class MyEvent {<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> private readonly TestClass _obj;<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> private readonly string _event;<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> internal MyEvent(TestClass obj, string eventStr) {<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> _obj = obj;<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> _event = eventStr;<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> }<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> [System.Runtime.CompilerServices.SpecialNameAttribute]<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> public object op_AdditionAssignment(EventHandler func) {<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> _obj.AttachEvent(_event, func);<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> return null;<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> }<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'> }<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='color:black'>}<o:p></o:p></span></p></div></div></body></html>