# Clr Interop and private member variables **URL:** \ **Category:** IronRuby\ **Created:** [May 5, 2009, 1:32am UTC](https://www.ruby-forum.com/t/clr-interop-and-private-member-variables/167170 "2009-05-05T01:32:43Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![Orion\_E](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/o/65b543/32.png) [@Orion\_E](https://www.ruby-forum.com/u/Orion_E)\ **Post date:** [May 5, 2009, 1:32am UTC](https://www.ruby-forum.com/t/clr-interop-and-private-member-variables/167170/1 "2009-05-05T01:32:43Z")
I have the following C# class namespace MyNamespace { public class MyObject { private string m\_Name; } } and I’m extending it from IronRuby class MyNameSpace::MyObject def printme puts m\_Name end end When I try to run this, I get undefined method `m\_Name’ for MyNameSpace::MyObject (NoMethodError) Other normal method/property calls work fine. Likewise if I do MyObject.new.instance\_eval{ m\_Name } the same error occurs. Is this because IronRuby is trying to call a method instead of read a member variable, or is it because the variable is private? Either way, is there a way I can fix this? (short of falling back to InvokeMember…) Thanks, Orion. ---
**Author:** ![Orion\_E](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/o/65b543/32.png) [@Orion\_E](https://www.ruby-forum.com/u/Orion_E)\ **Post date:** [May 5, 2009, 1:42am UTC](https://www.ruby-forum.com/t/clr-interop-and-private-member-variables/167170/2 "2009-05-05T01:42:05Z")
Make it protected instead of private? From: removed\_email\_address@domain.invalid [[mailto:removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)] On Behalf Of Orion E. Sent: Monday, May 04, 2009 4:32 PM To: removed\_email\_address@domain.invalid Subject: [Ironruby-core] Clr Interop and private member variables I have the following C# class namespace MyNamespace { public class MyObject { private string m\_Name; } } and I’m extending it from IronRuby class MyNameSpace::MyObject def printme puts m\_Name end end When I try to run this, I get undefined method `m\_Name’ for MyNameSpace::MyObject (NoMethodError) Other normal method/property calls work fine. Likewise if I do MyObject.new.instance\_eval{ m\_Name } the same error occurs. Is this because IronRuby is trying to call a method instead of read a member variable, or is it because the variable is private? Either way, is there a way I can fix this? (short of falling back to InvokeMember…) Thanks, Orion. ---
**Author:** ![Orion\_E](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/o/65b543/32.png) [@Orion\_E](https://www.ruby-forum.com/u/Orion_E)\ **Post date:** [May 5, 2009, 2:49am UTC](https://www.ruby-forum.com/t/clr-interop-and-private-member-variables/167170/3 "2009-05-05T02:49:20Z")
Yes, that’s right. As Jim said, you can use -X:PrivateBinding to work around this, but I don’t remember if this has any other consequences. From: removed\_email\_address@domain.invalid [[mailto:removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)] On Behalf Of Orion E. Sent: Monday, May 04, 2009 4:57 PM To: removed\_email\_address@domain.invalid Subject: Re: [Ironruby-core] Clr Interop and private member variables It’s not my code 🙂 It appears as though “extending” a class in ruby is more or less the same as creating a derived class… is this right? Might have to convince the other guy that “restricted by default” is not the best philosophy… On Tue, May 5, 2009 at 11:34 AM, Curt H. \ wrote: Make it protected instead of private? ---
**Author:** ![Orion\_E](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/o/65b543/32.png) [@Orion\_E](https://www.ruby-forum.com/u/Orion_E)\ **Post date:** [May 5, 2009, 3:01am UTC](https://www.ruby-forum.com/t/clr-interop-and-private-member-variables/167170/4 "2009-05-05T03:01:01Z")
PrivateBinding doesn’t mostly work in IronRuby yet (we will fix that). Note that the call to a private method/reading a private field will be much slower than if it was public. Also, it won’t work in partial trust (anywhere where your app is not granted full access to all .NET features, like in Silverlight, [ASP.NET](http://ASP.NET), etc.). I strongly suggest not to access private members unless you are writing unit tests for C# code. Tomas From: removed\_email\_address@domain.invalid [[mailto:removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)] On Behalf Of Curt Hagenlocher Sent: Monday, May 04, 2009 5:47 PM To: removed\_email\_address@domain.invalid Subject: Re: [Ironruby-core] Clr Interop and private member variables Yes, that’s right. As Jim said, you can use -X:PrivateBinding to work around this, but I don’t remember if this has any other consequences. From: removed\_email\_address@domain.invalid [[mailto:removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)] On Behalf Of Orion E. Sent: Monday, May 04, 2009 4:57 PM To: removed\_email\_address@domain.invalid Subject: Re: [Ironruby-core] Clr Interop and private member variables It’s not my code 🙂 It appears as though “extending” a class in ruby is more or less the same as creating a derived class… is this right? Might have to convince the other guy that “restricted by default” is not the best philosophy… On Tue, May 5, 2009 at 11:34 AM, Curt H. \ wrote: Make it protected instead of private? ---
**Author:** ![Orion\_E](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/o/65b543/32.png) [@Orion\_E](https://www.ruby-forum.com/u/Orion_E)\ **Post date:** [May 5, 2009, 1:57am UTC](https://www.ruby-forum.com/t/clr-interop-and-private-member-variables/167170/5 "2009-05-05T01:57:19Z")
It’s not my code 🙂 It appears as though “extending” a class in ruby is more or less the same as creating a derived class… is this right? Might have to convince the other guy that “restricted by default” is not the best philosophy…