Akka.Fsharp spawning an actor results in Exception in 1.3.6 release

[ivog]

The exception is:

System.Exception: Doesn't match
at Akka.FSharp.Linq.toExpression[Actor](Expression f)
at Akka.FSharp.Spawn.spawnOpt[Message,Returned](IActorRefFactory actorFactory, String name, FSharpFunc2 f, FSharpList1 options)

I think the problem could be related to the Akka.Fsharp project referencing the 1.1.0 version of FSharp.Quotations.Evaluator which is a broken package. The 1.1.2 version of that package is correct.

[ivog]

This is fixed since #3405 was merged. Since nightly build Akka.FSharp 1.3.7-beta501 Akka.Fsharp seems to be working properly again!

@chrisjhoare thanks! I guess PR #3441 wasn't even needed to fix Akka.FSharp. I'll close this issue.

[jtmueller]

I'm getting this error in 1.3.8...

[Aaronontheweb]

@jtmueller same exact stack trace? Do you have a small repro sample we could look at?

cc @Horusiath

[jtmueller]

@Aaronontheweb Yes, the same stack trace. I'm now getting it in 1.3.10 in a different project that I just updated from Akka 1.2.3. spawnObj appears to be completely unusable unless I stick to Akka 1.2.3.

at Akka.FSharp.Linq.toExpression[Actor](Expression f)
at Akka.FSharp.Spawn.spawnObjOpt[a](IActorRefFactory actorFactory, String name, FSharpExpr1 f, FSharpList1 options)

I can't share this project, but I guess I can try to make an isolated repro case if you still can't reproduce it. From where I'm sitting it's harder to avoid getting this error than it is to reproduce.

[jtmueller]

It might be relevant that my project is targeting .NET 4.5.2. However, I tried retargeting it to 4.6.1 and reinstalling all the nuget packages, but it didn't make any difference.

[jtmueller]

Here's a simple isolated repro: Akka.FSharp.SpawnRepro.zip

This project is targeting .NET 4.5.2 and Akka 1.2.3.

1. Open the attached project in Visual Studio 2017 (I have 15.9.3). Build and run it to verify that it works.
2. Use NuGet to upgrade Akka.FSharp to the latest version (or any version 1.3.6 or newer)
3. Now build and run again.

Unhandled Exception: System.Exception: Doesn't match
   at Akka.FSharp.Linq.toExpression[Actor](Expression f)
   at Akka.FSharp.Spawn.spawnObjOpt[a](IActorRefFactory actorFactory, String name, FSharpExpr`1 f, FSharpList`1 options)
   at Program.main(String[] argv) in C:\...\Akka.FSharp.SpawnRepro\Program.fs:line 16

[chrisjhoare]

Just opened a pull request which I appears to fix this. I'm not super familiar with this area and don't use expressions for actors myself, but at the very least you might be able to make use of the forked code yourself.

[Aaronontheweb]

Looks like @chrisjhoare's PR addresses this. Will be releasing that fix as part of 1.3.11, which we're going to be releasing shortly.

[Aaronontheweb]

closed via #3667