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So today I faced interesting problem while trying to build our company solution and I wanted to ask you guys do you know why is this happening. I've been told that it might be from my machine/visual studio because other people did not have same problem.

So we have a method in project A: 

private static string RpcRoutingKeyNamingConvention(Type messageType, ITypeNameSerializer typeNameSerializer)
{
   string queueName = typeNameSerializer.Serialize(messageType);

   return messageType.GetAttribute<GlobalRPCRequest>() != null || AvailabilityZone == null
        ? queueName
        : queueName + "_" + AvailabilityZone;
}

where GetAttribute<GlobalRPCRequest>() is defined in public static class ReflectionHelpers

 public static TAttribute GetAttribute<TAttribute>(this Type type) where TAttribute : Attribute;

then we have project B which have method:

public static string GetAttribute(this XElement node, string name)
{
   var xa = node.Attribute(name);
   return xa != null ? xa.Value : "";
}

I have to point out that we have reference to project B in project A. Now what happens is that when I try to build I get compile error:

Error 966 The type 'System.Xml.Linq.XElement' is defined in an assembly that is not referenced. You must add a reference to assembly 'System.Xml.Linq, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'. D:\Repositories\website\website\submodules\core\src\A\Extensions\Extensions.cs 37 13 A

Whats happening is that compiler thinks that I am actually using GetAttribute method from project B(in my opinion!). Why this is happening? Since when I try to navigate to GetAttribute VS leads me to the right method (the one that is in ReflectionHelpers). Could it be because of the reflection? NOTE: I fixed this issue by calling the method statically or adding reference to System.Xml.Linq in my project A, but I am curious of the strange behavior of VS/syntax-checking feature.

kuskmen
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  • Are you referencing the assembly containing XElement? Cuz its telling you _thats_ the problem; no method names mentioned. I mean did you try adding System.xml.linq? – D. Ben Knoble Apr 12 '16 at 18:14
  • Yes , I tried this actually fix the problem , but as I said we found the solution of this , but the strange behavior remains and I got curious. Plus adding reference to `System.XML.LINQ` it DOES solve the problem, but it is strange that compiler gets confused before that cause it is obvious(well maybe not that obvious to him) that I do not use any XElements. – kuskmen Apr 12 '16 at 19:03
  • But you do in project B? – D. Ben Knoble Apr 12 '16 at 19:12
  • No, I added the reference in project A. Project B was building with no problem. – kuskmen Apr 12 '16 at 19:15
  • Ah. Interesting. Editing what you told me in these comments into the question would greatly clarify for others – D. Ben Knoble Apr 12 '16 at 20:55
  • I am not sure but if you say so... its not like I am asking for solution of the error rather than asking for an explanation of the strange behavior. What does it matter how exactly I fixed it? – kuskmen Apr 12 '16 at 21:02
  • ??? It might spark some ones memory idk. I see it as potentially useful; you dont. Its your question. – D. Ben Knoble Apr 12 '16 at 21:03
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    http://stackoverflow.com/a/35940354/17034 – Hans Passant Apr 14 '16 at 15:53
  • Thanks man , that was exactly what was going on. – kuskmen Apr 14 '16 at 17:25

3 Answers3

1

It's a guess, but I think your function:

private static string RpcRoutingKeyNamingConvention(Type messageType, ITypeNameSerializer typeNameSerializer) does not match your helper method signature because you try returning a string:

public static TAttribute GetAttribute<TAttribute>(this Type type) where TAttribute : Attribute; which expects a TAttribute return type.

Maybe, you can try modifiying your function RpcRoutingKeyNamingConvention to return GlobalRPCRequest and check if the compiler continues to go crazy.

Yann RENAUDIN
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  • `does not match your helper method signature because you try returning a string:` what do you mean it doesn't match my helper method because I am trying to return string .. this is outrageous to state? – kuskmen Apr 21 '16 at 08:57
  • @Yann REANAUDIN He is not trying to return a string, look at `? queueName : queueName + "_" + AvailabilityZone;` – Tokk Apr 21 '16 at 11:40
1

Visual Studio gets confused all the times! I tried to reproduce the scenario in my VS 2015 (.NET 4.6) and it compiles just fine. I didn't have to add reference to System.Xml.Linq in my Project A.

My guess is that it might be a cache issue. You might want to try this:

  1. Remove reference to Project B
  2. Clean then rebuild both solutions
  3. Add the reference back
  4. Rebuild and voila!! Well.. hopefully

Hope it helps, let me know :)

kent-id
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0

I guess that's going on:
- B has reference to System.Xml.Linq
- B is built without a problem.
- You are referencing B in A
- A hasn't got a reference to System.Xml.Linq
- A seem to consume the function defined in B
- When you try to build project A, it produces that error

Am I right?

If that's the case, it is totally normal. Because a project which consumes a reference (A) must have a reference to what is referenced (System.Xml.Linq) by what it references (B).

Think like this: When you try to add a nuget package to your project if it has a dependency, nuget will install it too. Why? Because of this situation.

This is completely normal if I understand your answer correctly.

zokkan
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  • The question was why the compiler get confused that it will use function in project B when the navigation of visual studio clearly knows which one is the right method(the one in project A) ? When you answer this answer you will find answer to the original post answer at least that's how I got it. Check out the link in the comments below my question it pretty much answer all I am asking and wondering. – kuskmen Apr 20 '16 at 12:13
  • hahaha! sorry about my poor english (both for my answer and my confusion). You had right to do that :-) – zokkan Apr 20 '16 at 12:16
  • By the way, which version of vs you are using? – zokkan Apr 20 '16 at 12:19
  • do you have both versions namespaces in using block? did you try to call the method by providing the whole path? (ex: A.ReflectionHelpers.GetAttribute) – zokkan Apr 20 '16 at 12:22
  • Yes , I fixed the confusion of compiler with providing the whole path(a.k.a calling it statically.) The question is about the confusion not how to solve it. – kuskmen Apr 21 '16 at 08:55