Mailman 3 March 2006 - Python.NET

Naming and resolution of generic types (complete!)
by Brian Lloyd May 22, 2006

May 22, 2006

Hi all - I'm cross-posting this to the IP list as the subject seems to be an open issue there too. I'm working on generics support for Python for .NET, and there a couple of thorny issues that could use some discussion regarding naming and resolution of generic types. In C# you can explicitly name a generic type, a la Dictionary<,>. That syntax won't work in Python, of course. Looking at IP, it seems to allow the apparent Python name to be the unmangled IL name so you can naturally use the name. The problem is that the mangled name is illegal as a python name, and the unmangled name isn't guaranteed to be unique - you can potentially have any number of generic types as well as a non-generic type with the same base name in the same namespace: namespace Spam { public class SpamCan {} public class SpamCan<T> {} public class SpamCan<T, V> {} ... } I imagine that maybe IP has enough information available at compile-time to do the right thing for some common usage (binding and instantiating the types), but the overloaded name can still be ambiguous. A real-life example of this is System.IComparable - in IP, it doesn't seem possible to get to the non-generic version of IComparable anymore (or at least it was not obvious to me how to do it): >>> import System >>> System.IComparable <type 'IComparable`1'> It seems like we need to figure out some acceptable way of spelling generic type names explicitly in Python (an equivalent to IComparable<> in C#) that works within the existing syntax. There don't appear to be a lot of great options :( It has to be a valid Python name to work in an import statement, so that rules out strange operator shenanigans akin to the [] hack used for generic type binding. One would be to mimic the existing IL mangling in some way, a la: >From System import IComparable # the non-generic type >From System import IComparable_1 # the 1-param generic # or from System import IComparable_T from System.Collections.Generic import Dictionary_TT These are all pretty gross, and still don't totally prevent hiding of legit non-generic classes with those names (though it makes it less likely that names will be hidden than the current approach). I suppose another approach would be to continue to have only one type end up with the simple name, but provide a way to disambiguate it after the fact: >>> import System >>> System.IComparable <type 'IComparable`1'> >>> # abandon all hope, ye who enter here... >>> NonGenericIComparable = System.IComparable<<0 >>> OneParamGenericIComparable = System.IComparable<<1 >>> TwoParamVersionIfThereWasOne = System.IComparable<<2 That feels to me like it violates Python Zen in several ways, though. Thoughts? -Brian

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Delegates and Dictionaries
by Mark Anderson April 4, 2006

April 4, 2006

Hi all, I'm using .NET to implement a UI for some python code, and am updating various UI components using a .NET function. The .NET based UI calls the python based back end with an argument set which includes a delegate to the .NET UI update function. The python code then periodically invokes the delegate (passing it "a bunch of updated information") which is then used to update the UI. The problem is this: when "a bunch of updated information" is an integer, or a tuple, everything functions correctly. when "a bunch of updated information" is a python Dictionary, I receive the dreaded "TypeError: no method matches given arguments" message. I've tried explicitly typing the delegate argument as a PyDict, to no avail. Any suggestions? Thanks, Mark Anderson

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reg editor
by chatting chatting March 31, 2006

March 31, 2006

Hi What editor can i use for pythondot net. currently i am using Python2.4IDLE. while importing i will get error "no module " please let me know what editor and where i can download this. This will be very helpful for me. thanks Babu

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C# .net dll used in python
by Lalit DIGARI March 31, 2006

March 31, 2006

Hello All, I am trying to use a c# dll in python application I follows the following steps. import CLR from CLR.System.Reflection import Assembly my_dll_name = Assembly.LoadWithPartialName('VPCI') from CLR.System.Windows.Forms import Form from CLR.TestWinForm import Form1 VPCI = Form1()// Form1 is a class in my .net dll but I am getting CLR.system.DllNotFoundException:unalble to laod DLL(gpci.dll) While gpci.dll is defined in my .net application as [DllImport("gpcifunc.dll")] unsafe public static extern Int32 gpciOpen (Int32 dReserved) ; Form where the exception genrating Can any one help me out. 2) in case I am using my_dll_name = Assembly.LoadWithPartialName('path of dll') Then my_dll_name is getting none while I am keeping the dll in my python root path it is working fine Anyone has any clue. Regard's Lalit

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Re: [Python.NET] System.Data.dll
by f.kintzel March 30, 2006

March 30, 2006

Hi, I could not import System.Data too. The reason seems to be that the file System.Data.dll cannot be found by python. After copying it from C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\ to the working directory and it worked fine. best regards, Florian

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Re: [Python.NET] C# .net dll used in python
by Mark McMahon March 30, 2006

March 30, 2006

Hi, It would look to me like the gpcifunc.dll is a C dll not a .NET one? Isn't that what DllImport is for (note I do not know .NET very well - so I could be wrong). If it is a C Dll - then what you need to access that method is probably ctypes. Mark -----Original Message----- From: pythondotnet-bounces(a)python.org [mailto:pythondotnet-bounces@python.org] On Behalf Of Lalit DIGARI Sent: Thursday, March 30, 2006 7:05 AM To: pythondotnet(a)python.org Subject: [Python.NET] C# .net dll used in python Hello All, I am trying to use a c# dll in python application I follows the following steps. import CLR from CLR.System.Reflection import Assembly my_dll_name = Assembly.LoadWithPartialName('VPCI') from CLR.System.Windows.Forms import Form from CLR.TestWinForm import Form1 VPCI = Form1()// Form1 is a class in my .net dll but I am getting CLR.system.DllNotFoundException:unalble to laod DLL(gpci.dll) While gpci.dll is defined in my .net application as [DllImport("gpcifunc.dll")] unsafe public static extern Int32 gpciOpen (Int32 dReserved) ; Form where the exception genrating Can any one help me out. 2) in case I am using my_dll_name = Assembly.LoadWithPartialName('path of dll') Then my_dll_name is getting none while I am keeping the dll in my python root path it is working fine Anyone has any clue. Regard's Lalit _________________________________________________ Python.NET mailing list - PythonDotNet(a)python.org http://mail.python.org/mailman/listinfo/pythondotnet

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calling my assembly from python.net
by Mathew Yeates March 29, 2006

March 29, 2006

Hi I know I succeeded at this once before. But I just can't get it right. I have an assembly Test.dll with a namespace Foo. Inside Foo is a method called RunMe. What is the sequence of calls I need to do for me to call RunMe??? Mathew

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accessing .net dlls from python
by ivan Uemlianin March 29, 2006

March 29, 2006

Dear All I'm interested in accessing .net dlls from python (e.g. to write test scripts). Is pythonnet the correct software to use? I have had a go. I have installed pythonnet and tested it with some of the code samples: all well. Putting a .net dll called foo.dll in the current directory, 'import foo' raises the following error: ImportError: dynamic module does not define init function (initfoo) Is there a liitle bit extra I need to do, or am I barking up the wrong tree? I suppose I'm looking for something that will allow me to import .net dlls as if they were python modules. Any advice much appreciated. Best wishes Ivan

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Re: [Python.NET] accessing .net dlls from python
by Roman Yakovenko March 29, 2006

March 29, 2006

On 3/29/06, Lalit DIGARI <lalit.digari(a)st.com> wrote: > Hi Roman , Please write to the Python.Net mailing list, so other people can help you too. > I did the following step > import CLR > from CLR.System.Reflection import Assembly > > my_dll_name = Assembly.LoadWithPartialName('VPCILight') > > from CLR.System.Windows.Forms import Form > > from CLR.TestWinForm import Form1 > print my_dll_name > Form1.AutoSelectConv(1)** > > But not getting the way how to call AutoSelectConv(1) which is in > TestWinForm name space and memebr of the Form1 class how can I call it? What is the error you get? > Regard's > Lalit -- Roman Yakovenko C++ Python language binding http://www.language-binding.net/

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Re: [Python.NET] accessing .net dlls from python
by Roman Yakovenko March 29, 2006

March 29, 2006

On 3/29/06, Lalit DIGARI <lalit.digari(a)st.com> wrote: > Hello, > I have a dll named vp and I want to use it into python script dll has some > exposed function for example fn1() I did following steps in python > > import CLR > from CLR.System.Reflection import Assembly > > my_dll_name = Assembly.LoadWithPartialName('C:\\986tool\\vpci") > from CLR.System.Windows.Forms import Form > ##from CLR import TestWinForm > > my_dll_name.fn1(1) 1. I could be wrong, but .NET does not allows use of global functions. fn1 should be static function of some class 2. my_dll_name is instance of class Assembly, you can use it in order to call some function. ( Please re-check last statement, because I am not sure ). You should import it first. > > But I got two problems > 1) my_dll_name is coming none after call to LoadWithPartialName(...) > 2) the exposed function is name space TestWinForm as > using System; > using System.Drawing; > using System.Drawing.Imaging; > using System.Collections; > using System.ComponentModel; > using System.Windows.Forms; > using System.Data; > using System.Diagnostics ; > using System.Threading; > using System.Runtime.Serialization.Formatters.Binary ; > using System.IO ; > // ST Library > using STControlLibrary ; > using STImgPlatformLibrary ; > > > namespace TestWinForm > { > fn1() > { > } > } > > How will I import it into python script so that I can use exposed function. I think if you will resolve first issue and then write my_dll_name = Assembly.LoadWithPartialName('C:\\986tool\\vpci") from CLR import TestWinForm TestWinForm.GlobalFunctions.fn1(...) it will do the job. > If not clear then mail me back. > Thanks n regard's > Lalit -- Roman Yakovenko C++ Python language binding http://www.language-binding.net/

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