This may be stating the obvious, but I'll say it anyway because I've had many times when I missed something that should have been obvious, so maybe this will help you. But my guess is that the FSharp.NET.Sdk package contains Async extensions and/or implicit casts that cast from
Task to Async<unit> (and from Task<T> to Async<T>), and when the FSharp.NET.Sdk package was removed from the project file, you no longer had those implicit casts available so you had to convert from Task to Async<unit> manually.
I'm part of codewars.com
also I have a question on why I can't run Unit tests in visual studio 2017 for F#
I have been trying for the last 3 days and I have not found a solution yet
@MarkSchemmer - What unit test framework are you using? Nunit? Xunit? Expecto? Something else? Also, which version of the F# tools for VS 2017 are you running? I don't use Visual Studio myself so I can't help you with specifics, but I do know they had serious problems at first release (the VS 2017 build that became final had messed up on which version of the tools it included), and https://blogs.msdn.microsoft.com/dotnet/2017/03/14/announcing-nightly-releases-for-the-visual-f-tools/ strongly recommended running the nightly build. I don't know if that's still the case, but that might help. Finally, what precisely happens when you try to run unit tests? Do you get an error message, and if so, what is it? I think you'll need to provide more details of the problem before anyone will be able to help you. (And as I said, I don't use VS 2017 so the person who does end up helping you won't be me. But I can get the ball rolling by mentioning what other details you might need to provide.)
Ignore that code..
type IInterface<'T when 'T :> IInterface<'T>> =
abstract member Property : ICollection<IInterface<'T>>
type Implementor() =
interface IInterface<Implementor> with
member Property = List<Implementor>() :> ICollection<IInterface<Drop>>
Is there a reason why it is not possible to implement generic methods on a interface implementation?
type IMap =
abstract member Map: 'a -> 'b
type MapIntString() =
interface IMap with
member this.Map(x:int): string = sprintf "%i" x
type MapStringToInt() =
interface IMap with
member this.Map(x:string): int = 0I know I can
type IMap<'a, 'b> =
abstract member Map: 'a -> 'b
type MapIntString() =
interface IMap<int, string> with
member this.Map x = sprintf "%i" x
type MapStringToInt() =
interface Map<string, int> with
member this.Map (x:string): int = 0But that is not always possible or leads enormous amounts of code.
for example
type MapFoo(f: 'a -> 'b) =
interface Map with
member this.Map (x:Foo<'a>): Foo<'b> =
let (Foo a) = x
Foo (f a)In the above example at the moment I would have to create a specialized impl for any combination of 'a and 'b of Foo<_> whereas with an implementation like MapFoo I just need the functions that do the conversion and give one of these functions during construction time
So my question is: are there any hard technical limitations (CLR/.NET) or type theory or type inferrence that prevents this? And if so why is it even possible to define the interface like
type IMap =
abstract member Map: 'a -> 'bWhy not have a compiler error when trying to define a generic abstract method that uses generic types that are not defined on the type itself?
@robkuz https://stackoverflow.com/questions/8115470/creating-and-using-a-generic-function-in-a-non-generic-f-interface and http://codebetter.com/matthewpodwysocki/2009/05/08/type-classes-are-the-secret-sauce/ F# does not have type classes. So you can not have a generic Add interface that both Number and String implementations source from. I am not sure why it compiles the interface itself as it always needs an obj that you can not cast to (like int).
This way we could have completed control over time.
Is this the right place?
@robertmaxton42 ^
I see a dll and pdb file and stuff
K, I don't see a
.exe anywhere,
So I'm guessing I need to change a build setting or something?
Also thanks for your time!
I chose a Console Application
Alternatively you can try running the all although I'm a bit confused at this point :smile:
*dll=all
Hmm, didn't do anything.