Ship FSharp.Core with a net10.0 target framework

Directory.Build.props

@@ -74,6 +74,8 @@
        Cannot live in eng/TargetFrameworks.props because it's imported before Arcade. -->
   <PropertyGroup Condition="'$(DotNetBuildSourceOnly)' == 'true'">
     <FSharpNetCoreProductTargetFramework>$(NetCurrent)</FSharpNetCoreProductTargetFramework>
+    <!-- Source-build targets only $(NetCurrent); collapse the shipped-net pin to it (its ref pack is always present). -->
+    <FSharpCoreShippedNetTargetFramework>$(NetCurrent)</FSharpCoreShippedNetTargetFramework>
   </PropertyGroup>
 
   <!-- It's important we set TFM before this, since FSharpTests.Directory.Build.props uses it.

Directory.Build.targets

@@ -10,6 +10,13 @@
     <NoWarn>$(NoWarn);NU1507</NoWarn>
   </PropertyGroup>
 
+  <!-- net10.0 ships in the FSharp.Core package only; in-repo .NET consumers keep binding netstandard2.1. -->
+  <ItemGroup Condition="'$(TargetFrameworkIdentifier)' == '.NETCoreApp' and '$(Configuration)' != 'Proto'">
+    <ProjectReference Update="@(ProjectReference)">
+      <SetTargetFramework Condition="'%(ProjectReference.Filename)' == 'FSharp.Core' and '%(ProjectReference.SetTargetFramework)' == ''">TargetFramework=netstandard2.1</SetTargetFramework>
+    </ProjectReference>
+  </ItemGroup>
+
   <!-- Disable R2R when building source-only and not targeting the current SDK bundled TFM. -->
   <PropertyGroup>
     <PublishReadyToRun Condition="'$(DotNetBuildSourceOnly)' == 'true' and

azure-pipelines-PR.yml

@@ -562,6 +562,8 @@ stages:
           - script: .\Build.cmd -c Release -pack
             env:
               NativeToolsOnMachine: true
+          - script: .\eng\common\dotnet.cmd fsi .\tests\AheadOfTime\NetPackage\VerifyNetPackage.fsx -- .\artifacts\packages\Release
+            displayName: Verify FSharp.Core package assets
           - script: .\tests\EndToEndBuildTests\EndToEndBuildTests.cmd -c Release
             displayName: End to end build tests
 

docs/release-notes/.FSharp.Compiler.Service/11.0.100.md

@@ -30,6 +30,7 @@
 * Fix internal compiler error FS1110 in `task { let! }` (and other computation expressions) when a generic IL extension method whose `this`-parameter is a method-level type variable is in scope (e.g. `open ReactiveUI`). Regression from PR #19536. ([Issue #19936](https://github.com/dotnet/fsharp/issues/19936))
 * Fix inner mutually-recursive `let rec ... and ...` functions under `--realsig+` not being lifted to top-level static methods (TLR), causing `FSharpFunc` closure allocations and loss of `tail.` opcodes — the large struct-mutual-recursion perf regression reported in [Issue #17607](https://github.com/dotnet/fsharp/issues/17607). ([PR #19882](https://github.com/dotnet/fsharp/pull/19882))
 * Fix `TypeLoadException` ("Specialize tried to implicitly override a method with weaker type parameter constraints") and the related CLR crash with constrained inline calls by stripping constraints from closure-class typars in `EraseClosures.convIlxClosureDef`. ([Issue #14492](https://github.com/dotnet/fsharp/issues/14492), [Issue #19075](https://github.com/dotnet/fsharp/issues/19075), [PR #19882](https://github.com/dotnet/fsharp/pull/19882))
+* Fix FS0073 during code generation when closure generic arguments contain an unsolved type variable. ([PR #20229](https://github.com/dotnet/fsharp/pull/20229))
 * Fix `FieldAccessException` at runtime when the optimizer relocates a read of a `protected` (family) base-class field into a method outside the field's family (e.g. a trivial member inlined into module/startup code under `--optimize+`). Protected (family) IL field access is no longer hoisted out of its declaring family by inlining or method-splitting. ([Issue #19963](https://github.com/dotnet/fsharp/issues/19963), [PR #19964](https://github.com/dotnet/fsharp/pull/19964))
 
 * Suppress hover/symbol resolution for wildcard `_` patterns inside `member _.…` bodies that incorrectly showed `val _: T` tooltip. ([PR #19760](https://github.com/dotnet/fsharp/pull/19760))

docs/release-notes/.FSharp.Core/11.0.100.md

@@ -7,6 +7,7 @@
 
 ### Added
 
+* Ship `FSharp.Core` with an additional `net10.0` target framework (next to `netstandard2.0` and `netstandard2.1`). The `net`-TFM assembly is public-surface-identical to the `netstandard2.1` one; the target version is a pinned, deliberately advanced knob. ([PR #20229](https://github.com/dotnet/fsharp/pull/20229))
 * Add `Async.Await`, mirroring `Async.AwaitTask` semantics, but elides egregious `AggregateException` wrapping. Includes `ValueTask` support, and a SRTP-based overload accepting any Task-like value that supports the `GetAwaiter` protocol. ([Language Suggestion #840](https://github.com/fsharp/fslang-suggestions/issues/840), [PR #19785](https://github.com/dotnet/fsharp/pull/19785))
 * `Async.RunSynchronouslyImmediate`: runs work on the calling thread until the first asynchronous suspension (as opposed to `RunSynchronously`, which immediately offloads if not on a background and/or threadpool thread). ([Issue #1042](https://github.com/fsharp/fslang-suggestions/issues/1042), [PR #19804](https://github.com/dotnet/fsharp/pull/19804))
 * Added modules for `Async`, `Task` and `ValueTask` with consistent `result`, `map`, `bind`, `ignore`, `catchWith`, `catch`, and `empty` functions ([LanguageSuggestion #1466](https://github.com/fsharp/fslang-suggestions/issues/1466), [PR #19844](https://github.com/dotnet/fsharp/pull/19844))

eng/TargetFrameworks.props

@@ -15,6 +15,9 @@
 
     <!-- Derive major version by stripping 'net' prefix and '.0' suffix (e.g., net10.0 -> 10) -->
     <FSharpNetCoreProductMajorVersion>$([System.Text.RegularExpressions.Regex]::Replace('$(FSharpNetCoreProductTargetFramework)', '^net(\d+)\.0$', '$1'))</FSharpNetCoreProductMajorVersion>
+
+    <!-- Net TFM shipped in the FSharp.Core NuGet package. Lags the in-dev product TFM; bump deliberately. -->
+    <FSharpCoreShippedNetTargetFramework Condition="'$(FSharpCoreShippedNetTargetFramework)' == ''">net10.0</FSharpCoreShippedNetTargetFramework>
   </PropertyGroup>
 
 </Project>

src/Compiler/CodeGen/IlxGen.fs

@@ -6833,7 +6833,7 @@ and GenSequenceExpr
     let cloref = IlxClosureRef(ilCloTypeRef, ilCloLambdas, ilCloAllFreeVars)
 
     let ilxCloSpec =
-        IlxClosureSpec.Create(cloref, GenGenericArgs m eenvouter.tyenv cloFreeTyvars, false)
+        IlxClosureSpec.Create(cloref, GenGenericArgs cenv m eenvouter.tyenv cloFreeTyvars, false)
 
     let formalClospec =
         IlxClosureSpec.Create(cloref, mkILFormalGenericArgs 0 ilCloGenericParams, false)
@@ -7075,8 +7075,10 @@ and GenStaticDelegateClosureTypeDefs
 and GenGenericParams cenv eenv tps =
     tps |> DropErasedTypars |> List.map (GenGenericParam cenv eenv)
 
-and GenGenericArgs m (tyenv: TypeReprEnv) tps =
-    tps |> DropErasedTypars |> List.map (fun c -> (mkILTyvarTy tyenv[c, m]))
+and GenGenericArgs cenv m (tyenv: TypeReprEnv) tps =
+    tps
+    |> DropErasedTypars
+    |> List.map (fun tp -> GenType cenv m tyenv (mkTyparTy tp))
 
 /// Generate a local type function contract class and implementation
 and GenClosureAsLocalTypeFunction cenv (cgbuf: CodeGenBuffer) eenv thisVars expr m =
@@ -7476,7 +7478,7 @@ and GetIlxClosureInfo cenv m boxity isLocalTypeFunc canUseStaticField thisVars e
 
     /// Compute the contract if it is a local type function
     let ilCloGenericFormals = GenGenericParams cenv eenvinner cloFreeTyvars
-    let ilCloGenericActuals = GenGenericArgs m eenvouter.tyenv cloFreeTyvars
+    let ilCloGenericActuals = GenGenericArgs cenv m eenvouter.tyenv cloFreeTyvars
 
     let useStaticField = canUseStaticField && (ilCloAllFreeVars.Length = 0)
 
@@ -7784,7 +7786,7 @@ and GenDelegateExpr cenv cgbuf eenvouter expr (TObjExprMethod(slotsig, _attribs,
         CountClosure()
 
         // Push the constructor for the delegee
-        let ctxtGenericArgsForDelegee = GenGenericArgs m eenvouter.tyenv cloFreeTyvars
+        let ctxtGenericArgsForDelegee = GenGenericArgs cenv m eenvouter.tyenv cloFreeTyvars
 
         if useStaticClosure then
             GenUnit cenv eenvouter m cgbuf

src/FSharp.Core/FSharp.Core.fsproj

@@ -5,7 +5,7 @@
   <PropertyGroup>
     <OutputType>Library</OutputType>
     <TargetFrameworks Condition="'$(Configuration)' == 'Proto'">netstandard2.0</TargetFrameworks>
-    <TargetFrameworks Condition="'$(Configuration)' != 'Proto'">netstandard2.0;netstandard2.1</TargetFrameworks>
+    <TargetFrameworks Condition="'$(Configuration)' != 'Proto'">netstandard2.0;netstandard2.1;$(FSharpCoreShippedNetTargetFramework)</TargetFrameworks>
     <NoWarn>$(NoWarn);75</NoWarn> <!-- InternalCommandLineOption -->
     <NoWarn>$(NoWarn);1204</NoWarn> <!-- This construct is for use in the FSharp.Core library and should not be used directly -->
     <AllowCrossTargeting>true</AllowCrossTargeting>
@@ -36,6 +36,11 @@
     <Configurations>Debug;Release;Proto</Configurations>
   </PropertyGroup>
 
+  <!-- Surface the shipped-net pin to FSharp.Core.nuspec as a $token$. -->
+  <ItemGroup Condition="'$(Configuration)' != 'Proto'">
+    <NuspecProperty Include="FSharpCoreShippedNetTargetFramework=$(FSharpCoreShippedNetTargetFramework)" />
+  </ItemGroup>
+
     <!-- .FSharp.Core always uses the old style initialization mechanism because of SQL CLR requirements -->
   <PropertyGroup Condition="'$(BUILDING_USING_DOTNET)' != 'true' and '$(Configuration)' != 'Proto'">
     <OtherFlags>$(OtherFlags) --realsig-</OtherFlags>

src/FSharp.Core/FSharp.Core.nuspec

@@ -6,6 +6,7 @@
         <dependencies>
             <group targetFramework=".NETStandard2.0" />
             <group targetFramework=".NETStandard2.1" />
+            <group targetFramework="$FSharpCoreShippedNetTargetFramework$" />
         </dependencies>
     </metadata>
     <files>
@@ -22,5 +23,11 @@
 
         <!-- resources -->
         <file src="FSharp.Core\$Configuration$\netstandard2.1\**\FSharp.Core.resources.dll" target="lib\netstandard2.1" />
+
+        <file src="FSharp.Core\$Configuration$\$FSharpCoreShippedNetTargetFramework$\FSharp.Core.dll" target="lib\$FSharpCoreShippedNetTargetFramework$" />
+        <file src="FSharp.Core\$Configuration$\$FSharpCoreShippedNetTargetFramework$\FSharp.Core.xml" target="lib\$FSharpCoreShippedNetTargetFramework$" />
+
+        <!-- resources -->
+        <file src="FSharp.Core\$Configuration$\$FSharpCoreShippedNetTargetFramework$\**\FSharp.Core.resources.dll" target="lib\$FSharpCoreShippedNetTargetFramework$" />
     </files>
 </package>

src/FSharp.Core/Query.fs

@@ -107,7 +107,7 @@ type QueryBuilder() =
     member _.Head (source: QuerySource<'T, 'Q>) =
         Enumerable.First source.Source
 
-    member _.Nth (source: QuerySource<'T, 'Q>, index) =
+    member _.Nth (source: QuerySource<'T, 'Q>, index: int) =
         Enumerable.ElementAt (source.Source, index)
 
     member _.Skip (source: QuerySource<'T, 'Q>, count) : QuerySource<'T, 'Q> =
@@ -116,7 +116,7 @@ type QueryBuilder() =
     member _.SkipWhile (source: QuerySource<'T, 'Q>, predicate) : QuerySource<'T, 'Q> =
         QuerySource (Enumerable.SkipWhile (source.Source, Func<_, _>(predicate)))
 
-    member _.Take (source: QuerySource<'T, 'Q>, count) : QuerySource<'T, 'Q> =
+    member _.Take (source: QuerySource<'T, 'Q>, count: int) : QuerySource<'T, 'Q> =
         QuerySource (Enumerable.Take (source.Source, count))
 
     member _.TakeWhile (source: QuerySource<'T, 'Q>, predicate) : QuerySource<'T, 'Q> =
@@ -246,7 +246,7 @@ type QueryBuilder() =
         QuerySource (Enumerable.GroupJoin(outerSource.Source, innerSource.Source, Func<_, _>(outerKeySelector), Func<_, _>(innerKeySelector), Func<_, _, _>(resultSelector)))
 
     member _.LeftOuterJoin (outerSource: QuerySource<_, 'Q>, innerSource: QuerySource<_, 'Q>, outerKeySelector, innerKeySelector, resultSelector: _ ->  seq<_> -> _) : QuerySource<_, 'Q> =
-        QuerySource (Enumerable.GroupJoin(outerSource.Source, innerSource.Source, Func<_, _>(outerKeySelector), Func<_, _>(innerKeySelector), Func<_, _, _>(fun x g -> resultSelector x (g.DefaultIfEmpty()))))
+        QuerySource (Enumerable.GroupJoin(outerSource.Source, innerSource.Source, Func<_, _>(outerKeySelector), Func<_, _>(innerKeySelector), Func<_, _, _>(fun x (g: seq<_>) -> resultSelector x (g.DefaultIfEmpty()))))
 
     member _.RunQueryAsValue  (q: Quotations.Expr<'T>) : 'T =
         ForwardDeclarations.Query.Execute q
@@ -475,8 +475,8 @@ module Query =
         MakeOrCallContainsOrElementAt FQ FE
 
     let MakeElementAt, CallElementAt =
-        let FQ = methodhandleof (fun (x, y) -> Queryable.ElementAt(x, y))
-        let FE = methodhandleof (fun (x, y) -> Enumerable.ElementAt(x, y))
+        let FQ = methodhandleof (fun (x, y) -> Queryable.ElementAt(x, (y: int)))
+        let FE = methodhandleof (fun (x, y) -> Enumerable.ElementAt(x, (y: int)))
         MakeOrCallContainsOrElementAt FQ FE
 
     let MakeOrCallMinByOrMaxBy FQ FE =
@@ -886,8 +886,8 @@ module Query =
 
     let MakeTake =
         MakeSkipOrTake
-            (methodhandleof (fun (x, y) -> Queryable.Take (x, y)))
-            (methodhandleof (fun (x, y) -> Enumerable.Take (x, y)))
+            (methodhandleof (fun (x, y) -> Queryable.Take (x, (y: int))))
+            (methodhandleof (fun (x, y) -> Enumerable.Take (x, (y: int))))
 
     let MakeSkipWhile =
         GenMakeSkipWhileOrTakeWhile

src/FSharp.Core/async.fs

@@ -2254,7 +2254,7 @@ type Async =
     static member Await(task: Task) : Async<unit> =
         AwaitUnitTask true task
 
-#if NETSTANDARD2_1
+#if NETSTANDARD2_1 || NET
     static member Await(task: ValueTask<'T>) : Async<'T> =
         if task.IsCompletedSuccessfully then
             CreateReturnAsync(task.GetAwaiter().GetResult())

src/FSharp.Core/async.fsi

@@ -913,7 +913,7 @@ namespace Microsoft.FSharp.Control
         /// </example>
         static member Await: task: Task -> Async<unit>
 
-#if NETSTANDARD2_1
+#if NETSTANDARD2_1 || NET
         /// <summary>Creates an asynchronous computation that will wait for the given <c>ValueTask</c> to complete and return
         /// its result.</summary>
         /// <param name="task">The <c>ValueTask</c> to await.</param>
@@ -1291,13 +1291,13 @@ namespace Microsoft.FSharp.Control
             /// with <c>IsCompleted</c> and <c>GetResult()</c> members.</p>
             /// <p>Exceptions thrown by <c>GetResult()</c> are propagated directly.</p>
             /// <p>Unlike the <see cref="T:System.Threading.Tasks.Task"/>
-#if NETSTANDARD2_1
+#if NETSTANDARD2_1 || NET
             /// and <see cref="T:System.Threading.Tasks.ValueTask"/>
 #endif
             /// overloads, an <see cref="T:System.AggregateException"/> carrying multiple inner exceptions is not preserved:
             /// the first inner exception surfaces (standard <c>GetResult()</c> semantics).</p>
             /// <p>This overload uses statically resolved type parameters (SRTP) so it can accept any task-like type.
-#if NETSTANDARD2_1
+#if NETSTANDARD2_1 || NET
             /// The specific overloads for <see cref="T:System.Threading.Tasks.Task`1"/>, <see cref="T:System.Threading.Tasks.Task"/>,
             /// <see cref="T:System.Threading.Tasks.ValueTask`1"/> and <see cref="T:System.Threading.Tasks.ValueTask"/>
 #else
@@ -1931,4 +1931,3 @@ namespace Microsoft.FSharp.Control
         /// </example>
         [<CompiledName("Empty")>]
         val empty: Async<unit>
-

src/FSharp.Core/local.fs

@@ -10,17 +10,17 @@ module internal DetailedExceptions =
     open Microsoft.FSharp.Core
 
     /// takes an argument, a formatting string, a param array to splice into the formatting string
-    let inline invalidArgFmt (arg:string) (format:string) paramArray =
+    let inline invalidArgFmt (arg:string) (format:string) (paramArray: obj[]) =
         let msg = String.Format (format, paramArray)
         raise (ArgumentException(msg, arg))
 
     /// takes an argument, a formatting string, a param array to splice into the formatting string
-    let inline invalidArgOutOfRangeFmt (arg:string) (format:string) paramArray =
+    let inline invalidArgOutOfRangeFmt (arg:string) (format:string) (paramArray: obj[]) =
         let msg = String.Format (format, paramArray)
         raise (ArgumentOutOfRangeException(arg, msg))
 
     /// takes a formatting string and a param array to splice into the formatting string
-    let inline invalidOpFmt (format:string) paramArray =
+    let inline invalidOpFmt (format:string) (paramArray: obj[]) =
         let msg = String.Format (format, paramArray)
         raise (InvalidOperationException(msg))
 

src/FSharp.Core/prim-types.fs

@@ -443,13 +443,14 @@ namespace System.Diagnostics.CodeAnalysis
         member this.DynamicallyAccessedMembersAttribute(memberTypes: DynamicallyAccessedMemberTypes) =
             this.MemberTypes <- memberTypes
 
+#endif
+
 namespace Microsoft.FSharp.Core
     open System
     open System.Collections
     open System.Collections.Generic
     open System.Globalization
     open System.Reflection
-    #endif
 
     [<MeasureAnnotatedAbbreviation>] type float<[<Measure>] 'Measure> = float 
     [<MeasureAnnotatedAbbreviation>] type float32<[<Measure>] 'Measure> = float32
@@ -4096,6 +4097,7 @@ namespace Microsoft.FSharp.Core
     and 'T voption = ValueOption<'T>
 
 // These attributes only exist in .NET 8 and up.
+#if !NET8_0_OR_GREATER
 namespace System.Runtime.CompilerServices
     open System
     open Microsoft.FSharp.Core
@@ -4111,6 +4113,7 @@ namespace System.Runtime.CompilerServices
     [<AttributeUsage(AttributeTargets.Parameter, AllowMultiple = false, Inherited = false)>]
     type internal ScopedRefAttribute () =
         inherit Attribute ()
+#endif
 
 namespace Microsoft.FSharp.Collections
 
@@ -4128,7 +4131,7 @@ namespace Microsoft.FSharp.Collections
     open Microsoft.FSharp.Core.LanguagePrimitives.IntrinsicFunctions
     open Microsoft.FSharp.Core.BasicInlinedOperations
 
-#if NETSTANDARD2_1_OR_GREATER
+#if NETSTANDARD2_1_OR_GREATER || NET
     [<System.Runtime.CompilerServices.CollectionBuilder(typeof<List>, "Create")>]
 #endif
     [<DefaultAugmentation(false)>]
@@ -4156,7 +4159,7 @@ namespace Microsoft.FSharp.Collections
 
     and 'T list = List<'T>
 
-#if NETSTANDARD2_1_OR_GREATER
+#if NETSTANDARD2_1_OR_GREATER || NET
     and [<CompilerMessage("This type is for compiler use and should not be used directly", 1204, IsHidden=true);
           Sealed;
           AbstractClass;

src/FSharp.Core/prim-types.fsi

@@ -1008,6 +1008,7 @@ namespace Microsoft.FSharp.Core.CompilerServices
     [<CompilerMessage("This type is for compiler use and should not be used directly", 1204, IsHidden = true)>]
     type SupportsWhenTEnum = class end
 
+#if !NET5_0_OR_GREATER
 namespace System.Diagnostics.CodeAnalysis
 
     open System
@@ -1047,6 +1048,8 @@ namespace System.Diagnostics.CodeAnalysis
         new: DynamicallyAccessedMemberTypes -> DynamicallyAccessedMembersAttribute
         member MemberTypes: DynamicallyAccessedMemberTypes
 
+#endif
+
 namespace Microsoft.FSharp.Core
 
     open System
@@ -2606,6 +2609,7 @@ namespace Microsoft.FSharp.Core
       | Error of ErrorValue:'TError
 
 // These attributes only exist in .NET 8 and up.
+#if !NET8_0_OR_GREATER
 namespace System.Runtime.CompilerServices
     open System
     open Microsoft.FSharp.Core
@@ -2637,6 +2641,7 @@ namespace System.Runtime.CompilerServices
     type internal ScopedRefAttribute =
         inherit Attribute
         new: unit -> ScopedRefAttribute
+#endif
 
 namespace Microsoft.FSharp.Collections
 
@@ -2654,7 +2659,7 @@ namespace Microsoft.FSharp.Collections
     /// </remarks>
     ///
     /// <exclude />
-#if NETSTANDARD2_1_OR_GREATER
+#if NETSTANDARD2_1_OR_GREATER || NET
     [<System.Runtime.CompilerServices.CollectionBuilder(typeof<List>, "Create")>]
 #endif
     [<DefaultAugmentation(false)>]
@@ -2730,7 +2735,7 @@ namespace Microsoft.FSharp.Collections
     /// </remarks>
     and 'T list = List<'T>
 
-#if NETSTANDARD2_1_OR_GREATER
+#if NETSTANDARD2_1_OR_GREATER || NET
     /// <summary>Contains methods for compiler use related to lists.</summary>
     and [<CompilerMessage("This type is for compiler use and should not be used directly", 1204, IsHidden=true);
           Sealed;

src/FSharp.Core/set.fs

@@ -768,7 +768,7 @@ module internal SetTree =
     let ofArray comparer l =
         Array.fold (fun acc k -> add comparer k acc) empty l
 
-#if NETSTANDARD2_1_OR_GREATER
+#if NETSTANDARD2_1_OR_GREATER || NET
 [<System.Runtime.CompilerServices.CollectionBuilder(typeof<Set>, "Create")>]
 #endif
 [<Sealed>]
@@ -1097,7 +1097,7 @@ type Set<[<EqualityConditionalOn>] 'T when 'T: comparison>(comparer: IComparer<'
                 .Append("; ... ]")
                 .ToString()
 
-#if NETSTANDARD2_1_OR_GREATER
+#if NETSTANDARD2_1_OR_GREATER || NET
 and [<CompilerMessage("This type is for compiler use and should not be used directly", 1204, IsHidden = true);
       Sealed;
       AbstractClass;