Unpublish C# 8 patterns (#49549)

* Unpublish C# 8 patterns

The ECMA committee merged dotnet/csharpstandard#873

Now, remove the feature spec from publication.

* Fix warnings

* Remove C# 8 feature spec references

It's all in the standard now.

Author: BillWagner

.openpublishing.redirection.csharp.json

@@ -108,26 +108,6 @@
             "source_path_from_root": "/redirections/proposals/csharp-7.3/tuple-equality.md",
             "redirect_url": "/dotnet/csharp/language-reference/language-specification/expressions#121211-tuple-equality-operators"
         },
-        {
-            "source_path_from_root": "/redirections/proposals/csharp-8.0/nullable-reference-types.md",
-            "redirect_url": "/dotnet/csharp/language-reference/language-specification/types#893-nullable-reference-types"
-        },
-        {
-            "source_path_from_root": "/redirections/proposals/csharp-8.0/nested-stackalloc.md",
-            "redirect_url": "/dotnet/csharp/language-reference/language-specification/structs#164127-stackalloc"
-        },
-        {
-            "source_path_from_root": "/redirections/proposals/csharp-8.0/readonly-instance-members.md",
-            "redirect_url": "/dotnet/csharp/language-reference/language-specification/structs#16411-properties"
-        },
-        {
-            "source_path_from_root": "/redirections/proposals/csharp-8.0/null-coalescing-assignment.md",
-            "redirect_url": "/dotnet/csharp/language-reference/language-specification/expressions#1222-assignment-operators"
-        },
-        {
-            "source_path_from_root": "/redirections/proposals/csharp-8.0/async-streams.md",
-            "redirect_url": "/dotnet/csharp/language-reference/language-specification/statements#13953-await-foreach"
-        },
         {
             "source_path_from_root": "/redirections/proposals/csharp-9.0/nullable-reference-types-specification.md",
             "redirect_url": "/dotnet/csharp/language-reference/language-specification/types#893-nullable-reference-types"
@@ -1473,18 +1453,6 @@
             "source_path_from_root": "/docs/csharp/language-reference/proposals/csharp-7.3/index.md",
             "redirect_url": "/dotnet/csharp/language-reference/proposals/csharp-7.3/ref-local-reassignment"
         },
-        {
-            "source_path_from_root": "/docs/csharp/language-reference/proposals/csharp-8.0/index.md",
-            "redirect_url": "/dotnet/csharp/language-reference/language-specification/types#893-nullable-reference-types"
-        },
-        {
-            "source_path_from_root": "/docs/csharp/language-reference/proposals/csharp-8.0/static-local-functions.md",
-            "redirect_url": "/dotnet/csharp/language-reference/language-specification/statements#1364-local-function-declarations"
-        },
-        {
-            "source_path_from_root": "/docs/csharp/language-reference/proposals/csharp-8.0/nullable-reference-types.md",
-            "redirect_url": "/dotnet/csharp/language-reference/language-specification/types#893-nullable-reference-types"
-        },
         {
             "source_path_from_root": "/docs/csharp/language-reference/proposals/csharp-9.0/nullable-reference-types-specification.md",
             "redirect_url": "/dotnet/csharp/language-reference/language-specification/types#893-nullable-reference-types"

docfx.json

@@ -48,7 +48,6 @@
             },
             {
                 "files": [
-                    "csharp-8.0/*.md",
                     "csharp-9.0/*.md",
                     "csharp-10.0/*.md",
                     "csharp-11.0/*.md",
@@ -62,24 +61,6 @@
                     "**/README.md",
                     "inactive/**",
                     "rejected/**",
-                    "csharp-8.0/alternative-interpolated-verbatim.md",
-                    "csharp-8.0/async-using.md",
-                    "csharp-8.0/constraints-in-overrides.md",
-                    "csharp-8.0/constructed-unmanaged.md",
-                    "csharp-8.0/notnull-constraint.md",
-                    "csharp-8.0/obsolete-accessor.md",
-                    "csharp-8.0/shadowing-in-nested-functions.md",
-                    "csharp-8.0/static-local-functions.md",
-                    "csharp-8.0/unconstrained-null-coalescing.md",
-                    "csharp-8.0/nullable-reference-types.md",
-                    "csharp-8.0/nullable-reference-types-specification.md",
-                    "csharp-8.0/nested-stackalloc.md",
-                    "csharp-8.0/readonly-instance-members.md",
-                    "csharp-8.0/null-coalescing-assignment.md",
-                    "csharp-8.0/async-streams.md",
-                    "csharp-8.0/ranges.md",
-                    "csharp-8.0/using.md",
-                    "csharp-8.0/default-interface-methods.md",
                     "csharp-9.0/nullable-reference-types-specification.md",
                     "csharp-9.0/nullable-constructor-analysis.md",
                     "csharp-9.0/nullable-parameter-default-value-analysis.md",
@@ -524,7 +505,6 @@
             },
             "ms.date": {
                 "_csharpstandard/standard/*.md": "09/12/2025",
-                "_csharplang/proposals/csharp-8.0/*.md": "09/10/2019",
                 "_csharplang/proposals/csharp-9.0/*.md": "07/29/2020",
                 "_csharplang/proposals/csharp-10.0/*.md": "08/07/2021",
                 "_csharplang/proposals/csharp-11.0/*.md": "09/30/2022",
@@ -638,7 +618,6 @@
                 "_csharpstandard/standard/standard-library.md": "Standard library",
                 "_csharpstandard/standard/documentation-comments.md": "Documentation comments",
                 "_csharpstandard/standard/Bibliography.md": "Bibliography",
-                "_csharplang/proposals/csharp-8.0/patterns.md": "Recursive pattern matching",
                 "_csharplang/proposals/csharp-9.0/covariant-returns.md": "Covariant return types",
                 "_csharplang/proposals/csharp-9.0/extending-partial-methods.md": "Extending partial methods",
                 "_csharplang/proposals/csharp-9.0/extension-getenumerator.md": "Extension GetEnumerator support in foreach",
@@ -765,7 +744,6 @@
                 "_csharpstandard/standard/standard-library.md": "This appendix lists requirements of the specification library. The C# language relies on these types for some of its behavior.",
                 "_csharpstandard/standard/documentation-comments.md": "This appendix describes XML comments that are used to document your program.",
                 "_csharpstandard/standard/Bibliography.md": "This appendix lists external standards referenced in this specification.",
-                "_csharplang/proposals/csharp-8.0/patterns.md": "This feature specification describes recursive pattern matching, where patterns can nest inside other patterns.",
                 "_csharplang/proposals/csharp-9.0/covariant-returns.md": "This feature specification describes covariant return types, where overriding member declarations can return a type derived from the overridden member declaration.",
                 "_csharplang/proposals/csharp-9.0/extending-partial-methods.md": "This feature specification describes extensions to partial methods. These extensions enable source generators to create or call partial methods.",
                 "_csharplang/proposals/csharp-9.0/extension-getenumerator.md": "This feature specification describes the necessary pattern for an extension method to provide the GetEnumerator support in a foreach loop.",
@@ -861,7 +839,6 @@
             "titleSuffix": {
                 "docs/**/*.md": ".NET",
                 "_csharpstandard/standard/*.md": "C# language specification",
-                "_csharplang/proposals/csharp-8.0/*.md": "C# feature specifications",
                 "_csharplang/proposals/csharp-9.0/*.md": "C# feature specifications",
                 "_csharplang/proposals/csharp-10.0/*.md": "C# feature specifications",
                 "_csharplang/proposals/csharp-11.0/*.md": "C# feature specifications",

docs/csharp/language-reference/builtin-types/enum.md

@@ -88,8 +88,8 @@ For more information, see the following sections of the [C# language specificati
 
 - [Enums](~/_csharpstandard/standard/enums.md)
 - [Enum values and operations](~/_csharpstandard/standard/enums.md#206-enum-values-and-operations)
-- [Enumeration logical operators](~/_csharpstandard/standard/expressions.md#12143-enumeration-logical-operators)
-- [Enumeration comparison operators](~/_csharpstandard/standard/expressions.md#12136-enumeration-comparison-operators)
+- [Enumeration logical operators](~/_csharpstandard/standard/expressions.md#12153-enumeration-logical-operators)
+- [Enumeration comparison operators](~/_csharpstandard/standard/expressions.md#12146-enumeration-comparison-operators)
 - [Explicit enumeration conversions](~/_csharpstandard/standard/conversions.md#1033-explicit-enumeration-conversions)
 - [Implicit enumeration conversions](~/_csharpstandard/standard/conversions.md#1024-implicit-enumeration-conversions)
 

docs/csharp/language-reference/builtin-types/nullable-reference-types.md

@@ -72,10 +72,7 @@ There are two ways to control the nullable context. At the project level, you ca
 
 ## C# language specification
 
-For more information, see the following proposals for the [C# language specification](~/_csharpstandard/standard/README.md):
-
-- [Nullable reference types](~/_csharplang/proposals/csharp-8.0/nullable-reference-types.md)
-- [Draft nullable reference types specification](~/_csharplang/proposals/csharp-9.0/nullable-reference-types-specification.md)
+For more information, see the [Nullable reference types](~/_csharpstandard/standard/types.md#89-reference-types-and-nullability) section of the [C# language specification](~/_csharpstandard/standard/README.md):
 
 ## See also
 

docs/csharp/language-reference/builtin-types/struct.md

@@ -172,8 +172,8 @@ For more information, see the [Structs](~/_csharpstandard/standard/structs.md) s
 
 For more information about `struct` features, see the following feature proposal notes:
 
-- [Readonly structs](~/_csharplang/proposals/csharp-7.2/readonly-ref.md#readonly-structs)
-- [Readonly instance members](~/_csharplang/proposals/csharp-8.0/readonly-instance-members.md)
+- [Readonly structs](~/_csharpstandard/standard/structs.md#1622-struct-modifiers)
+- [Readonly instance members](~/_csharpstandard/standard/structs.md#163-struct-members)
 - [Parameterless struct constructors](~/_csharplang/proposals/csharp-10.0/parameterless-struct-constructors.md)
 - [Allow `with` expression on structs](~/_csharplang/proposals/csharp-10.0/record-structs.md#allow-with-expression-on-structs)
 - [Record structs](~/_csharplang/proposals/csharp-10.0/record-structs.md)

docs/csharp/language-reference/compiler-messages/overloaded-operator-errors.md

@@ -298,7 +298,7 @@ To fix these errors, remove invalid conversion operators or restructure your typ
 - **CS0217**: *In order to be applicable as a short-circuit operator, a user-defined logical operator must have the same return type as the type of its 2 parameters.*
 - **CS0218**: *The type must contain declarations of operator true and operator false.*
 
-These errors occur when you define logical operators incorrectly. Certain operators must be defined in pairs, and short-circuit operators have specific signature requirements. For more information, see [true and false operators](../operators/true-false-operators.md), [Boolean logical operators](../operators/boolean-logical-operators.md), and [User-defined conditional logical operators](~/_csharpstandard/standard/expressions.md#12153-user-defined-conditional-logical-operators). The following code demonstrates these errors:
+These errors occur when you define logical operators incorrectly. Certain operators must be defined in pairs, and short-circuit operators have specific signature requirements. For more information, see [true and false operators](../operators/true-false-operators.md), [Boolean logical operators](../operators/boolean-logical-operators.md), and [User-defined conditional logical operators](~/_csharpstandard/standard/expressions.md#12163-user-defined-conditional-logical-operators). The following code demonstrates these errors:
 
 ```csharp
 class C

docs/csharp/language-reference/keywords/const.md

@@ -63,7 +63,7 @@ The following example demonstrates how to declare a local constant:
 For more information, see the following sections of the [C# language specification](~/_csharpstandard/standard/README.md):
 
 - [Constants](~/_csharpstandard/standard/classes.md#154-constants)
-- [Constant expressions](~/_csharpstandard/standard/expressions.md#1224-constant-expressions)
+- [Constant expressions](~/_csharpstandard/standard/expressions.md#1225-constant-expressions)
 
 ## See also
 

docs/csharp/language-reference/keywords/interface.md

@@ -40,7 +40,6 @@ An interface declaration can contain the following members:
 - [A static constructor](../../programming-guide/classes-and-structs/constructors.md#static-constructors).
 - [Nested types](../../programming-guide/classes-and-structs/nested-types.md).
 - [Static fields, methods, properties, indexers, and events](static.md).
-- [Member declarations using the explicit interface implementation syntax](~/_csharplang/proposals/csharp-8.0/default-interface-methods.md#explicit-implementation-in-interfaces).
 - Explicit access modifiers (the default access for abstract methods is [`public`](access-modifiers.md)).
 
 ## Default interface members
@@ -90,7 +89,7 @@ The following example demonstrates interface implementation. In this example, th
 
 ## C# language specification
 
-For more information, see the [Interfaces](~/_csharpstandard/standard/interfaces.md) section of the [C# language specification](~/_csharpstandard/standard/README.md), the feature specification for [C# 8 - Default interface members](~/_csharplang/proposals/csharp-8.0/default-interface-methods.md), and the feature spec for [C# 11 - static abstract members in interfaces](~/_csharplang/proposals/csharp-11.0/static-abstracts-in-interfaces.md).
+For more information, see the [Interfaces](~/_csharpstandard/standard/interfaces.md) section of the [C# language specification](~/_csharpstandard/standard/README.md) and the feature spec for [C# 11 - static abstract members in interfaces](~/_csharplang/proposals/csharp-11.0/static-abstracts-in-interfaces.md).
 
 ## See also
 

docs/csharp/language-reference/keywords/readonly.md

@@ -97,11 +97,6 @@ The method essentially returns a `readonly` reference together with the instance
 
 [!INCLUDE[CSharplangspec](~/includes/csharplangspec-md.md)]
 
-You can also see the language specification proposals:
-
-- [readonly ref and readonly struct](~/_csharplang/proposals/csharp-7.2/readonly-ref.md)
-- [readonly struct members](~/_csharplang/proposals/csharp-8.0/readonly-instance-members.md)
-
 ## See also
 
 - [Add readonly modifier (style rule IDE0044)](../../../fundamentals/code-analysis/style-rules/ide0044.md)

docs/csharp/language-reference/operators/addition-operator.md

@@ -72,7 +72,7 @@ A user-defined type can [overload](operator-overloading.md) the `+` operator. Wh
 
 ## C# language specification
 
-For more information, see the [Unary plus operator](~/_csharpstandard/standard/expressions.md#1292-unary-plus-operator) and [Addition operator](~/_csharpstandard/standard/expressions.md#12115-addition-operator) sections of the [C# language specification](~/_csharpstandard/standard/README.md). For more information on overloading the compound assignment operators in C# 14 and later, see the [user defined compound assignment](~/_csharplang/proposals/csharp-14.0/user-defined-compound-assignment.md) feature specification.
+For more information, see the [Unary plus operator](~/_csharpstandard/standard/expressions.md#1292-unary-plus-operator) and [Addition operator](~/_csharpstandard/standard/expressions.md#12125-addition-operator) sections of the [C# language specification](~/_csharpstandard/standard/README.md). For more information on overloading the compound assignment operators in C# 14 and later, see the [user defined compound assignment](~/_csharplang/proposals/csharp-14.0/user-defined-compound-assignment.md) feature specification.
 
 ## See also