From 35bf49b1e76dabe5a013173dabb3bce3093f50f4 Mon Sep 17 00:00:00 2001
From: Adam Sitnik <adam.sitnik@gmail.com>
Date: Mon, 13 Mar 2023 15:20:09 +0100
Subject: [PATCH 1/5] remove SetHandler overloads

---
 ...ommandLine_api_is_not_changed.approved.txt |  18 --
 .../CommandLine/Perf_Parser_Simple.cs         |   6 +-
 .../EndToEndTestApp/Program.cs                |  16 +-
 src/System.CommandLine.Tests/ArgumentTests.cs |   2 +-
 .../Binding/SetHandlerTests.cs                | 209 +-----------------
 .../EnvironmentVariableDirectiveTests.cs      |  14 +-
 .../GlobalOptionTests.cs                      |   4 +-
 .../Invocation/InvocationExtensionsTests.cs   |   8 +-
 .../Invocation/InvocationPipelineTests.cs     |  22 +-
 .../ParserTests.MultiplePositions.cs          |   2 +-
 .../ParsingValidationTests.cs                 |   8 +-
 .../UseExceptionHandlerTests.cs               |   4 +-
 src/System.CommandLine.Tests/UseHelpTests.cs  |   2 +-
 .../VersionOptionTests.cs                     |  18 +-
 src/System.CommandLine/Handler.Action.cs      | 185 ----------------
 src/System.CommandLine/Handler.Func.cs        | 185 ----------------
 src/System.CommandLine/Handler.cs             |  26 ---
 17 files changed, 59 insertions(+), 670 deletions(-)
 delete mode 100644 src/System.CommandLine/Handler.cs

diff --git a/src/System.CommandLine.ApiCompatibility.Tests/ApiCompatibilityApprovalTests.System_CommandLine_api_is_not_changed.approved.txt b/src/System.CommandLine.ApiCompatibility.Tests/ApiCompatibilityApprovalTests.System_CommandLine_api_is_not_changed.approved.txt
index 73e49a9e72..abc07ddebf 100644
--- a/src/System.CommandLine.ApiCompatibility.Tests/ApiCompatibilityApprovalTests.System_CommandLine_api_is_not_changed.approved.txt
+++ b/src/System.CommandLine.ApiCompatibility.Tests/ApiCompatibilityApprovalTests.System_CommandLine_api_is_not_changed.approved.txt
@@ -110,25 +110,7 @@ System.CommandLine
     .ctor()
   public static class Handler
     public static System.Void SetHandler(this Command command, System.Action<System.CommandLine.Invocation.InvocationContext> handle)
-    public static System.Void SetHandler(this Command command, System.Action handle)
-    public static System.Void SetHandler(this Command command, System.Func<System.Threading.CancellationToken,System.Threading.Tasks.Task> handle)
     public static System.Void SetHandler(this Command command, System.Func<System.CommandLine.Invocation.InvocationContext,System.Threading.CancellationToken,System.Threading.Tasks.Task> handle)
-    public static System.Void SetHandler<T>(this Command command, Action<T> handle, IValueDescriptor<T> symbol)
-    public static System.Void SetHandler<T>(this Command command, Func<T,System.Threading.CancellationToken,System.Threading.Tasks.Task> handle, IValueDescriptor<T> symbol)
-    public static System.Void SetHandler<T1, T2>(this Command command, Action<T1,T2> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2)
-    public static System.Void SetHandler<T1, T2>(this Command command, Func<T1,T2,System.Threading.CancellationToken,System.Threading.Tasks.Task> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2)
-    public static System.Void SetHandler<T1, T2, T3>(this Command command, Action<T1,T2,T3> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3)
-    public static System.Void SetHandler<T1, T2, T3>(this Command command, Func<T1,T2,T3,System.Threading.CancellationToken,System.Threading.Tasks.Task> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3)
-    public static System.Void SetHandler<T1, T2, T3, T4>(this Command command, Action<T1,T2,T3,T4> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4)
-    public static System.Void SetHandler<T1, T2, T3, T4>(this Command command, Func<T1,T2,T3,T4,System.Threading.CancellationToken,System.Threading.Tasks.Task> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4)
-    public static System.Void SetHandler<T1, T2, T3, T4, T5>(this Command command, Action<T1,T2,T3,T4,T5> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4, IValueDescriptor<T5> symbol5)
-    public static System.Void SetHandler<T1, T2, T3, T4, T5>(this Command command, Func<T1,T2,T3,T4,T5,System.Threading.CancellationToken,System.Threading.Tasks.Task> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4, IValueDescriptor<T5> symbol5)
-    public static System.Void SetHandler<T1, T2, T3, T4, T5, T6>(this Command command, Action<T1,T2,T3,T4,T5,T6> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4, IValueDescriptor<T5> symbol5, IValueDescriptor<T6> symbol6)
-    public static System.Void SetHandler<T1, T2, T3, T4, T5, T6>(this Command command, Func<T1,T2,T3,T4,T5,T6,System.Threading.CancellationToken,System.Threading.Tasks.Task> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4, IValueDescriptor<T5> symbol5, IValueDescriptor<T6> symbol6)
-    public static System.Void SetHandler<T1, T2, T3, T4, T5, T6, T7>(this Command command, Action<T1,T2,T3,T4,T5,T6,T7> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4, IValueDescriptor<T5> symbol5, IValueDescriptor<T6> symbol6, IValueDescriptor<T7> symbol7)
-    public static System.Void SetHandler<T1, T2, T3, T4, T5, T6, T7>(this Command command, Func<T1,T2,T3,T4,T5,T6,T7,System.Threading.CancellationToken,System.Threading.Tasks.Task> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4, IValueDescriptor<T5> symbol5, IValueDescriptor<T6> symbol6, IValueDescriptor<T7> symbol7)
-    public static System.Void SetHandler<T1, T2, T3, T4, T5, T6, T7, T8>(this Command command, Action<T1,T2,T3,T4,T5,T6,T7,T8> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4, IValueDescriptor<T5> symbol5, IValueDescriptor<T6> symbol6, IValueDescriptor<T7> symbol7, IValueDescriptor<T8> symbol8)
-    public static System.Void SetHandler<T1, T2, T3, T4, T5, T6, T7, T8>(this Command command, Func<T1,T2,T3,T4,T5,T6,T7,T8,System.Threading.CancellationToken,System.Threading.Tasks.Task> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4, IValueDescriptor<T5> symbol5, IValueDescriptor<T6> symbol6, IValueDescriptor<T7> symbol7, IValueDescriptor<T8> symbol8)
   public interface ICommandHandler
     public System.Int32 Invoke(System.CommandLine.Invocation.InvocationContext context)
     public System.Threading.Tasks.Task<System.Int32> InvokeAsync(System.CommandLine.Invocation.InvocationContext context, System.Threading.CancellationToken cancellationToken = null)
diff --git a/src/System.CommandLine.Benchmarks/CommandLine/Perf_Parser_Simple.cs b/src/System.CommandLine.Benchmarks/CommandLine/Perf_Parser_Simple.cs
index ffe283f11b..9c0cb8bc83 100644
--- a/src/System.CommandLine.Benchmarks/CommandLine/Perf_Parser_Simple.cs
+++ b/src/System.CommandLine.Benchmarks/CommandLine/Perf_Parser_Simple.cs
@@ -33,7 +33,11 @@ private static RootCommand BuildCommand()
                 stringOption
             };
 
-            command.SetHandler(static (bool _, string _) => { }, boolOption, stringOption);
+            command.SetHandler(ctx => 
+            {
+                bool boolean = ctx.ParseResult.GetValue(boolOption);
+                string text = ctx.ParseResult.GetValue(stringOption);
+            });
 
             return command;
         }
diff --git a/src/System.CommandLine.Suggest.Tests/EndToEndTestApp/Program.cs b/src/System.CommandLine.Suggest.Tests/EndToEndTestApp/Program.cs
index 02f4da77fd..85626fc381 100644
--- a/src/System.CommandLine.Suggest.Tests/EndToEndTestApp/Program.cs
+++ b/src/System.CommandLine.Suggest.Tests/EndToEndTestApp/Program.cs
@@ -1,4 +1,5 @@
 using System.CommandLine;
+using System.CommandLine.Invocation;
 using System.CommandLine.Parsing;
 using System.Threading.Tasks;
 using System.Threading;
@@ -22,12 +23,15 @@ static async Task Main(string[] args)
                 durianOption,          
             };
 
-            rootCommand.SetHandler(
-                (string apple, string banana, string cherry, string durian, CancellationToken cancellationToken) => Task.CompletedTask,
-                appleOption,
-                bananaOption,
-                cherryOption,
-                durianOption);
+            rootCommand.SetHandler((InvocationContext ctx, CancellationToken cancellationToken) =>
+            {
+                string apple = ctx.ParseResult.GetValue(appleOption);
+                string banana = ctx.ParseResult.GetValue(bananaOption);
+                string cherry = ctx.ParseResult.GetValue(cherryOption);
+                string durian = ctx.ParseResult.GetValue(durianOption);
+
+                return Task.CompletedTask;
+            });
 
             var commandLine = new CommandLineBuilder(rootCommand)
                 .UseDefaults()
diff --git a/src/System.CommandLine.Tests/ArgumentTests.cs b/src/System.CommandLine.Tests/ArgumentTests.cs
index 6bc7d9d649..b32dcbd796 100644
--- a/src/System.CommandLine.Tests/ArgumentTests.cs
+++ b/src/System.CommandLine.Tests/ArgumentTests.cs
@@ -378,7 +378,7 @@ public async Task Custom_argument_parser_is_only_called_once()
                 };
 
                 var command = new RootCommand();
-                command.SetHandler((int value) => handlerWasCalled = true, option);
+                command.SetHandler((ctx) => handlerWasCalled = true);
                 command.Options.Add(option);
 
                 await command.InvokeAsync("--value 42");
diff --git a/src/System.CommandLine.Tests/Binding/SetHandlerTests.cs b/src/System.CommandLine.Tests/Binding/SetHandlerTests.cs
index beb956865d..9b0dc3a409 100644
--- a/src/System.CommandLine.Tests/Binding/SetHandlerTests.cs
+++ b/src/System.CommandLine.Tests/Binding/SetHandlerTests.cs
@@ -3,6 +3,7 @@
 
 using System.Collections.Generic;
 using System.CommandLine.Binding;
+using System.CommandLine.Invocation;
 using System.CommandLine.IO;
 using System.CommandLine.Parsing;
 using System.Linq;
@@ -15,31 +16,6 @@ namespace System.CommandLine.Tests.Binding
 {
     public class SetHandlerTests
     {
-        [Fact]
-        public void Custom_types_can_be_bound()
-        {
-            var boolOption = new Option<int>("-i");
-            var stringArg = new Argument<string>("value");
-
-            var command = new RootCommand
-            {
-                boolOption,
-                stringArg
-            };
-
-            CustomType boundInstance = default;
-            command.SetHandler(
-                (CustomType instance) => boundInstance = instance,
-                new CustomBinder(boolOption, stringArg));
-
-            var console = new TestConsole();
-            command.Invoke("-i 123 hi", console);
-
-            boundInstance.IntValue.Should().Be(123);
-            boundInstance.StringValue.Should().Be("hi");
-            boundInstance.Console.Should().NotBeNull();
-        }
-
         public class CustomType
         {
             public string StringValue { get; set; }
@@ -71,187 +47,6 @@ protected override CustomType GetBoundValue(BindingContext bindingContext)
             }
         }
 
-        [Theory]
-        [InlineData(1)]
-        [InlineData(2)]
-        [InlineData(3)]
-        [InlineData(4)]
-        [InlineData(5)]
-        [InlineData(6)]
-        [InlineData(7)]
-        [InlineData(8)]
-        public void Binding_is_correct_for_Action_overload_having_arity_(int arity)
-        {
-            var command = new RootCommand();
-            var commandLine = "";
-
-            for (var i = 1; i <= arity; i++)
-            {
-                command.Arguments.Add(new Argument<int>($"i{i}"));
-
-                commandLine += $" {i}";
-            }
-
-            var receivedValues = new List<int>();
-            Delegate handlerFunc = arity switch
-            {
-                1 => new Action<int>(
-                    i1 =>
-                        Received(i1)),
-                2 => new Action<int, int>(
-                    (i1, i2) =>
-                        Received(i1, i2)),
-                3 => new Action<int, int, int>(
-                    (i1, i2, i3) =>
-                        Received(i1, i2, i3)),
-                4 => new Action<int, int, int, int>(
-                    (i1, i2, i3, i4) =>
-                        Received(i1, i2, i3, i4)),
-                5 => new Action<int, int, int, int, int>(
-                    (i1, i2, i3, i4, i5) =>
-                        Received(i1, i2, i3, i4, i5)),
-                6 => new Action<int, int, int, int, int, int>(
-                    (i1, i2, i3, i4, i5, i6) =>
-                        Received(i1, i2, i3, i4, i5, i6)),
-                7 => new Action<int, int, int, int, int, int, int>(
-                    (i1, i2, i3, i4, i5, i6, i7) =>
-                        Received(i1, i2, i3, i4, i5, i6, i7)),
-                8 => new Action<int, int, int, int, int, int, int, int>(
-                    (i1, i2, i3, i4, i5, i6, i7, i8) =>
-                        Received(i1, i2, i3, i4, i5, i6, i7, i8)),
-              
-                _ => throw new ArgumentOutOfRangeException()
-            };
-
-            // build up the method invocation
-            var genericMethodDef = typeof(Handler)
-                                   .GetMethods()
-                                   .Where(m => m.Name == nameof(Handler.SetHandler))
-                                   .Where(m => m.IsGenericMethod /* symbols + handler Func */)
-                                   .Where(m => m.GetParameters().ElementAt(1).ParameterType.Name.StartsWith("Action"))
-                                   .Single(m => m.GetGenericArguments().Length == arity);
-
-            var genericParameterTypes = Enumerable.Range(1, arity)
-                                                  .Select(_ => typeof(int))
-                                                  .ToArray();
-
-            var setHandler = genericMethodDef.MakeGenericMethod(genericParameterTypes);
-
-            var parameters = new List<object>
-            {
-                command,
-                handlerFunc
-            };
-
-            parameters.AddRange(command.Arguments);
-
-            setHandler.Invoke(null, parameters.ToArray());
-
-            var exitCode = command.Invoke(commandLine);
-
-            receivedValues.Should().BeEquivalentTo(
-                Enumerable.Range(1, arity),
-                config => config.WithStrictOrdering());
-
-            exitCode.Should().Be(0);
-
-            Task Received(params int[] values)
-            {
-                receivedValues.AddRange(values);
-                return Task.CompletedTask;
-            }
-        }
-
-        [Theory]
-        [InlineData(1)]
-        [InlineData(2)]
-        [InlineData(3)]
-        [InlineData(4)]
-        [InlineData(5)]
-        [InlineData(6)]
-        [InlineData(7)]
-        [InlineData(8)]
-        public void Binding_is_correct_for_Func_overload_having_arity_(int arity)
-        {
-            var command = new RootCommand();
-            var commandLine = "";
-
-            for (var i = 1; i <= arity; i++)
-            {
-                command.Arguments.Add(new Argument<int>($"i{i}"));
-
-                commandLine += $" {i}";
-            }
-
-            var receivedValues = new List<int>();
-            Delegate handlerFunc = arity switch
-            {
-                1 => new Func<int, CancellationToken, Task>(
-                    (i1, cancellationToken) =>
-                        Received(i1)),
-                2 => new Func<int, int, CancellationToken, Task>(
-                    (i1, i2, cancellationToken) =>
-                        Received(i1, i2)),
-                3 => new Func<int, int, int, CancellationToken, Task>(
-                    (i1, i2, i3, cancellationToken) =>
-                        Received(i1, i2, i3)),
-                4 => new Func<int, int, int, int, CancellationToken, Task>(
-                    (i1, i2, i3, i4, cancellationToken) =>
-                        Received(i1, i2, i3, i4)),
-                5 => new Func<int, int, int, int, int, CancellationToken, Task>(
-                    (i1, i2, i3, i4, i5, cancellationToken) =>
-                        Received(i1, i2, i3, i4, i5)),
-                6 => new Func<int, int, int, int, int, int, CancellationToken, Task>(
-                    (i1, i2, i3, i4, i5, i6, cancellationToken) =>
-                        Received(i1, i2, i3, i4, i5, i6)),
-                7 => new Func<int, int, int, int, int, int, int, CancellationToken, Task>(
-                    (i1, i2, i3, i4, i5, i6, i7, cancellationToken) =>
-                        Received(i1, i2, i3, i4, i5, i6, i7)),
-                8 => new Func<int, int, int, int, int, int, int, int, CancellationToken, Task>(
-                    (i1, i2, i3, i4, i5, i6, i7, i8, cancellationToken) =>
-                        Received(i1, i2, i3, i4, i5, i6, i7, i8)),
-             
-                _ => throw new ArgumentOutOfRangeException()
-            };
-
-            // build up the method invocation
-            var genericMethodDef = typeof(Handler)
-                                   .GetMethods()
-                                   .Where(m => m.Name == nameof(Handler.SetHandler))
-                                   .Where(m => m.IsGenericMethod /* symbols + handler Func */)
-                                   .Where(m => m.GetParameters().ElementAt(1).ParameterType.Name.StartsWith("Func"))
-                                   .Single(m => m.GetGenericArguments().Length == arity);
-
-            var genericParameterTypes = Enumerable.Range(1, arity)
-                                                  .Select(_ => typeof(int))
-                                                  .ToArray();
-
-            var setHandler = genericMethodDef.MakeGenericMethod(genericParameterTypes);
-
-            var parameters = new List<object>
-            {
-                command,
-                handlerFunc,
-            };
-            parameters.AddRange(command.Arguments);
-
-            setHandler.Invoke(null, parameters.ToArray());
-            
-            var exitCode = command.Invoke(commandLine);
-
-            receivedValues.Should().BeEquivalentTo(
-                Enumerable.Range(1, arity),
-                config => config.WithStrictOrdering());
-
-            exitCode.Should().Be(123);
-
-            Task Received(params int[] values)
-            {
-                receivedValues.AddRange(values);
-                return Task.FromResult(123);
-            }
-        }
-
         [Fact]
         public async Task Unexpected_return_types_result_in_exit_code_0_if_no_exception_was_thrown()
         {
@@ -259,7 +54,7 @@ public async Task Unexpected_return_types_result_in_exit_code_0_if_no_exception_
 
             var command = new Command("wat");
 
-            var handle = (CancellationToken cancellationToken) =>
+            var handle = (InvocationContext ctx, CancellationToken cancellationToken) =>
             {
                 wasCalled = true;
                 return Task.FromResult(new { NovelType = true });
diff --git a/src/System.CommandLine.Tests/EnvironmentVariableDirectiveTests.cs b/src/System.CommandLine.Tests/EnvironmentVariableDirectiveTests.cs
index 0ca5fa347b..b66b53dabe 100644
--- a/src/System.CommandLine.Tests/EnvironmentVariableDirectiveTests.cs
+++ b/src/System.CommandLine.Tests/EnvironmentVariableDirectiveTests.cs
@@ -19,7 +19,7 @@ public async Task Sets_environment_variable_to_value()
             string variable = test_variable;
             const string value = "This is a test";
             var rootCommand = new RootCommand();
-            rootCommand.SetHandler(() =>
+            rootCommand.SetHandler((_) =>
             {
                 asserted = true;
                 Environment.GetEnvironmentVariable(variable).Should().Be(value);
@@ -41,7 +41,7 @@ public async Task Trims_environment_variable_name()
             string variable = test_variable;
             const string value = "This is a test";
             var rootCommand = new RootCommand();
-            rootCommand.SetHandler(() =>
+            rootCommand.SetHandler((_) =>
             {
                 asserted = true;
                 Environment.GetEnvironmentVariable(variable).Should().Be(value);
@@ -63,7 +63,7 @@ public async Task Trims_environment_variable_value()
             string variable = test_variable;
             const string value = "This is a test";
             var rootCommand = new RootCommand();
-            rootCommand.SetHandler(() =>
+            rootCommand.SetHandler((_) =>
             {
                 asserted = true;
                 Environment.GetEnvironmentVariable(variable).Should().Be(value);
@@ -85,7 +85,7 @@ public async Task Sets_environment_variable_value_containing_equals_sign()
             string variable = test_variable;
             const string value = "This is = a test containing equals";
             var rootCommand = new RootCommand();
-            rootCommand.SetHandler(() =>
+            rootCommand.SetHandler((_) =>
             {
                 asserted = true;
                 Environment.GetEnvironmentVariable(variable).Should().Be(value);
@@ -106,7 +106,7 @@ public async Task Ignores_environment_directive_without_equals_sign()
             bool asserted = false;
             string variable = test_variable;
             var rootCommand = new RootCommand();
-            rootCommand.SetHandler(() =>
+            rootCommand.SetHandler((_) =>
             {
                 asserted = true;
                 Environment.GetEnvironmentVariable(variable).Should().BeNull();
@@ -127,7 +127,7 @@ public static async Task Ignores_environment_directive_with_empty_variable_name(
             bool asserted = false;
             string value = $"This is a test, random: {randomizer.Next()}";
             var rootCommand = new RootCommand();
-            rootCommand.SetHandler(() =>
+            rootCommand.SetHandler((_) =>
             {
                 asserted = true;
                 var env = Environment.GetEnvironmentVariables();
@@ -149,7 +149,7 @@ public static async Task Ignores_environment_directive_with_whitespace_variable_
             bool asserted = false;
             string value = $"This is a test, random: {randomizer.Next()}";
             var rootCommand = new RootCommand();
-            rootCommand.SetHandler(() =>
+            rootCommand.SetHandler((_) =>
             {
                 asserted = true;
                 var env = Environment.GetEnvironmentVariables();
diff --git a/src/System.CommandLine.Tests/GlobalOptionTests.cs b/src/System.CommandLine.Tests/GlobalOptionTests.cs
index ee4212bfe1..63e068b72c 100644
--- a/src/System.CommandLine.Tests/GlobalOptionTests.cs
+++ b/src/System.CommandLine.Tests/GlobalOptionTests.cs
@@ -29,7 +29,7 @@ public void When_a_required_global_option_is_omitted_it_results_in_an_error()
         {
             var command = new Command("child");
             var rootCommand = new RootCommand { command };
-            command.SetHandler(() => { });
+            command.SetHandler((_) => { });
             var requiredOption = new Option<bool>("--i-must-be-set")
             {
                 IsRequired = true,
@@ -69,7 +69,7 @@ public void When_a_required_global_option_is_present_on_child_of_command_it_was_
         {
             var command = new Command("child");
             var rootCommand = new RootCommand { command };
-            command.SetHandler(() => { });
+            command.SetHandler((_) => { });
             var requiredOption = new Option<bool>("--i-must-be-set")
             {
                 IsRequired = true,
diff --git a/src/System.CommandLine.Tests/Invocation/InvocationExtensionsTests.cs b/src/System.CommandLine.Tests/Invocation/InvocationExtensionsTests.cs
index 9308314cc1..c1f315b753 100644
--- a/src/System.CommandLine.Tests/Invocation/InvocationExtensionsTests.cs
+++ b/src/System.CommandLine.Tests/Invocation/InvocationExtensionsTests.cs
@@ -52,7 +52,7 @@ public async Task RootCommand_InvokeAsync_returns_0_when_handler_is_successful()
             var wasCalled = false;
             var rootCommand = new RootCommand();
 
-            rootCommand.SetHandler(() => wasCalled = true);
+            rootCommand.SetHandler((_) => wasCalled = true);
 
             var result = await rootCommand.InvokeAsync("");
 
@@ -66,7 +66,7 @@ public void RootCommand_Invoke_returns_0_when_handler_is_successful()
             var wasCalled = false;
             var rootCommand = new RootCommand();
 
-            rootCommand.SetHandler(() => wasCalled = true);
+            rootCommand.SetHandler((_) => wasCalled = true);
 
             int result = rootCommand.Invoke("");
 
@@ -80,7 +80,7 @@ public async Task RootCommand_InvokeAsync_returns_1_when_handler_throws()
             var wasCalled = false;
             var rootCommand = new RootCommand();
 
-            rootCommand.SetHandler(_ =>
+            rootCommand.SetHandler((_, __) =>
             {
                 wasCalled = true;
                 throw new Exception("oops!");
@@ -103,7 +103,7 @@ public void RootCommand_Invoke_returns_1_when_handler_throws()
             var wasCalled = false;
             var rootCommand = new RootCommand();
 
-            rootCommand.SetHandler(_ =>
+            rootCommand.SetHandler((_, __) =>
             {
                 wasCalled = true;
                 throw new Exception("oops!");
diff --git a/src/System.CommandLine.Tests/Invocation/InvocationPipelineTests.cs b/src/System.CommandLine.Tests/Invocation/InvocationPipelineTests.cs
index 98b014bd9a..1076923f85 100644
--- a/src/System.CommandLine.Tests/Invocation/InvocationPipelineTests.cs
+++ b/src/System.CommandLine.Tests/Invocation/InvocationPipelineTests.cs
@@ -39,10 +39,10 @@ public async Task InvokeAsync_chooses_the_appropriate_command()
             var secondWasCalled = false;
 
             var first = new Command("first");
-            first.SetHandler(() => firstWasCalled = true);
+            first.SetHandler((_) => firstWasCalled = true);
 
             var second = new Command("second");
-            second.SetHandler(() => secondWasCalled = true);
+            second.SetHandler((_) => secondWasCalled = true);
 
             var config = new CommandLineBuilder(new RootCommand
                          {
@@ -64,10 +64,10 @@ public void Invoke_chooses_the_appropriate_command()
             var secondWasCalled = false;
 
             var first = new Command("first");
-            first.SetHandler(() => firstWasCalled = true);
+            first.SetHandler((_) => firstWasCalled = true);
 
             var second = new Command("second");
-            second.SetHandler(() => secondWasCalled = true);
+            second.SetHandler((_) => secondWasCalled = true);
 
             var config = new CommandLineBuilder(new RootCommand
                          {
@@ -120,14 +120,14 @@ public void When_middleware_throws_then_Invoke_does_not_handle_the_exception()
         public void When_command_handler_throws_then_InvokeAsync_does_not_handle_the_exception()
         {
             var command = new Command("the-command");
-            command.SetHandler(_ =>
-                {
-                    throw new Exception("oops!");
-                    // Help the compiler pick a CommandHandler.Create overload.
+            command.SetHandler((_, __) =>
+            {
+                throw new Exception("oops!");
+                // Help the compiler pick a CommandHandler.Create overload.
 #pragma warning disable CS0162 // Unreachable code detected
-                    return Task.FromResult(0);
+                return Task.FromResult(0);
 #pragma warning restore CS0162
-                });
+            });
 
             var config = new CommandLineBuilder(new RootCommand
                          {
@@ -149,7 +149,7 @@ public void When_command_handler_throws_then_InvokeAsync_does_not_handle_the_exc
         public void When_command_handler_throws_then_Invoke_does_not_handle_the_exception()
         {
             var command = new Command("the-command");
-            command.SetHandler(_ =>
+            command.SetHandler((_, __) =>
             {
                 throw new Exception("oops!");
                 // Help the compiler pick a CommandHandler.Create overload.
diff --git a/src/System.CommandLine.Tests/ParserTests.MultiplePositions.cs b/src/System.CommandLine.Tests/ParserTests.MultiplePositions.cs
index 85739ef226..77b7266a2d 100644
--- a/src/System.CommandLine.Tests/ParserTests.MultiplePositions.cs
+++ b/src/System.CommandLine.Tests/ParserTests.MultiplePositions.cs
@@ -118,7 +118,7 @@ public void A_command_can_be_specified_in_more_than_one_position(
                 string expectedParent)
             {
                 var reusedCommand = new Command("reused");
-                reusedCommand.SetHandler(() => { });
+                reusedCommand.SetHandler((_) => { });
                 reusedCommand.Add(new Option<string>("--the-option"));
 
                 var outer = new Command("outer")
diff --git a/src/System.CommandLine.Tests/ParsingValidationTests.cs b/src/System.CommandLine.Tests/ParsingValidationTests.cs
index 07119ea452..c773d772ec 100644
--- a/src/System.CommandLine.Tests/ParsingValidationTests.cs
+++ b/src/System.CommandLine.Tests/ParsingValidationTests.cs
@@ -514,9 +514,9 @@ public async Task A_custom_validator_added_to_a_global_option_is_checked(string
 
             rootCommand.Options.Add(globalOption);
 
-            rootCommand.SetHandler((int i) => handlerWasCalled = true, globalOption);
-            childCommand.SetHandler((int i) => handlerWasCalled = true, globalOption);
-            grandchildCommand.SetHandler((int i) => handlerWasCalled = true, globalOption);
+            rootCommand.SetHandler((ctx) => handlerWasCalled = true);
+            childCommand.SetHandler((ctx) => handlerWasCalled = true);
+            grandchildCommand.SetHandler((ctx) => handlerWasCalled = true);
 
             var result = await rootCommand.InvokeAsync(commandLine);
 
@@ -1145,7 +1145,7 @@ public void A_command_with_subcommands_is_valid_to_invoke_if_it_has_a_handler()
         {
             var outer = new Command("outer");
             var inner = new Command("inner");
-            inner.SetHandler(() => { });
+            inner.SetHandler((_) => { });
             var innerer = new Command("inner-er");
             outer.Subcommands.Add(inner);
             inner.Subcommands.Add(innerer);
diff --git a/src/System.CommandLine.Tests/UseExceptionHandlerTests.cs b/src/System.CommandLine.Tests/UseExceptionHandlerTests.cs
index c1fd66824a..744185c856 100644
--- a/src/System.CommandLine.Tests/UseExceptionHandlerTests.cs
+++ b/src/System.CommandLine.Tests/UseExceptionHandlerTests.cs
@@ -53,7 +53,7 @@ public async Task UseExceptionHandler_catches_middleware_exceptions_and_writes_d
         public async Task UseExceptionHandler_catches_command_handler_exceptions_and_sets_result_code_to_1()
         {
             var command = new Command("the-command");
-            command.SetHandler(_ =>
+            command.SetHandler((_, __) =>
             {
                 throw new Exception("oops!");
                 // Help the compiler pick a CommandHandler.Create overload.
@@ -78,7 +78,7 @@ public async Task UseExceptionHandler_catches_command_handler_exceptions_and_set
         public async Task UseExceptionHandler_catches_command_handler_exceptions_and_writes_details_to_standard_error()
         {
             var command = new Command("the-command");
-            command.SetHandler(_ =>
+            command.SetHandler((_, __) =>
             {
                 throw new Exception("oops!");
                 // Help the compiler pick a CommandHandler.Create overload.
diff --git a/src/System.CommandLine.Tests/UseHelpTests.cs b/src/System.CommandLine.Tests/UseHelpTests.cs
index 76cf5e05b3..353770b564 100644
--- a/src/System.CommandLine.Tests/UseHelpTests.cs
+++ b/src/System.CommandLine.Tests/UseHelpTests.cs
@@ -46,7 +46,7 @@ public async Task UseHelp_interrupts_execution_of_the_specified_command()
             var wasCalled = false;
             var command = new Command("command");
             var subcommand = new Command("subcommand");
-            subcommand.SetHandler(() => wasCalled = true);
+            subcommand.SetHandler((_) => wasCalled = true);
             command.Subcommands.Add(subcommand);
 
             var config =
diff --git a/src/System.CommandLine.Tests/VersionOptionTests.cs b/src/System.CommandLine.Tests/VersionOptionTests.cs
index 73ff3655b4..9624286caa 100644
--- a/src/System.CommandLine.Tests/VersionOptionTests.cs
+++ b/src/System.CommandLine.Tests/VersionOptionTests.cs
@@ -37,7 +37,7 @@ public async Task When_the_version_option_is_specified_then_invocation_is_short_
         {
             var wasCalled = false;
             var rootCommand = new RootCommand();
-            rootCommand.SetHandler(() => wasCalled = true);
+            rootCommand.SetHandler((_) => wasCalled = true);
 
             var config = new CommandLineBuilder(rootCommand)
                          .UseVersionOption()
@@ -78,7 +78,7 @@ public async Task When_the_version_option_is_specified_and_there_are_default_opt
                     DefaultValueFactory = (_) => true
                 }
             };
-            rootCommand.SetHandler(() => { });
+            rootCommand.SetHandler((_) => { });
 
             var configuration = new CommandLineBuilder(rootCommand)
                 .UseVersionOption()
@@ -98,7 +98,7 @@ public async Task When_the_version_option_is_specified_and_there_are_default_arg
             {
                 new Argument<bool>("x") { DefaultValueFactory =(_) => true }
             };
-            rootCommand.SetHandler(() => { });
+            rootCommand.SetHandler((_) => { });
 
             var configuration = new CommandLineBuilder(rootCommand)
                 .UseVersionOption()
@@ -117,13 +117,13 @@ public async Task When_the_version_option_is_specified_and_there_are_default_arg
         public void Version_is_not_valid_with_other_tokens(string commandLine)
         {
             var subcommand = new Command("subcommand");
-            subcommand.SetHandler(() => { });
+            subcommand.SetHandler((_) => { });
             var rootCommand = new RootCommand
             {
                 subcommand,
                 new Option<bool>("-x")
             };
-            rootCommand.SetHandler(() => { });
+            rootCommand.SetHandler((_) => { });
 
             var configuration = new CommandLineBuilder(rootCommand)
                 .UseVersionOption()
@@ -138,13 +138,13 @@ public void Version_is_not_valid_with_other_tokens(string commandLine)
         public void Version_option_is_not_added_to_subcommands()
         {
             var childCommand = new Command("subcommand");
-            childCommand.SetHandler(() => { });
+            childCommand.SetHandler((_) => { });
 
             var rootCommand = new RootCommand
             {
                 childCommand,
             };
-            rootCommand.SetHandler(() => { });
+            rootCommand.SetHandler((_) => { });
 
             var configuration = new CommandLineBuilder(rootCommand)
                          .UseVersionOption()
@@ -198,12 +198,12 @@ public async Task Version_can_specify_additional_alias()
         public void Version_is_not_valid_with_other_tokens_uses_custom_alias()
         {
             var childCommand = new Command("subcommand");
-            childCommand.SetHandler(() => { });
+            childCommand.SetHandler((_) => { });
             var rootCommand = new RootCommand
             {
                 childCommand
             };
-            rootCommand.SetHandler(() => { });
+            rootCommand.SetHandler((_) => { });
 
             var configuration = new CommandLineBuilder(rootCommand)
                          .UseVersionOption("-v")
diff --git a/src/System.CommandLine/Handler.Action.cs b/src/System.CommandLine/Handler.Action.cs
index ed7039beb0..2812339f3f 100644
--- a/src/System.CommandLine/Handler.Action.cs
+++ b/src/System.CommandLine/Handler.Action.cs
@@ -1,7 +1,6 @@
 // Copyright (c) .NET Foundation and contributors. All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
-using System.CommandLine.Binding;
 using System.CommandLine.Invocation;
 
 namespace System.CommandLine;
@@ -18,188 +17,4 @@ public static void SetHandler(
         this Command command,
         Action<InvocationContext> handle) =>
         command.Handler = new AnonymousCommandHandler(handle);
-
-    /// <summary>
-    /// Sets a command's handler based on an <see cref="Action"/>.
-    /// </summary>
-    public static void SetHandler(
-        this Command command,
-        Action handle) =>
-        command.Handler = new AnonymousCommandHandler(_ => handle());
-
-    /// <summary>
-    /// Sets a command's handler based on an <see cref="Action{T}"/>.
-    /// </summary>
-    public static void SetHandler<T>(
-        this Command command,
-        Action<T> handle,
-        IValueDescriptor<T> symbol) =>
-        command.Handler = new AnonymousCommandHandler(
-            context =>
-            {
-                var value1 = GetValueForHandlerParameter(symbol, context);
-
-                handle(value1!);
-            });
-
-    /// <summary>
-    /// Sets a command's handler based on an <see cref="Action{T1,T2}"/>.
-    /// </summary>
-    public static void SetHandler<T1, T2>(
-        this Command command,
-        Action<T1, T2> handle,
-        IValueDescriptor<T1> symbol1,
-        IValueDescriptor<T2> symbol2) =>
-        command.Handler = new AnonymousCommandHandler(
-            context =>
-            {
-                var value1 = GetValueForHandlerParameter(symbol1, context);
-                var value2 = GetValueForHandlerParameter(symbol2, context);
-
-                handle(value1!, value2!);
-            });
-
-    /// <summary>
-    /// Sets a command's handler based on an <see cref="Action{T1,T2,T3}"/>.
-    /// </summary>
-    public static void SetHandler<T1, T2, T3>(
-        this Command command,
-        Action<T1, T2, T3> handle,
-        IValueDescriptor<T1> symbol1,
-        IValueDescriptor<T2> symbol2,
-        IValueDescriptor<T3> symbol3) =>
-        command.Handler = new AnonymousCommandHandler(
-            context =>
-            {
-                var value1 = GetValueForHandlerParameter(symbol1, context);
-                var value2 = GetValueForHandlerParameter(symbol2, context);
-                var value3 = GetValueForHandlerParameter(symbol3, context);
-
-                handle(value1!, value2!, value3!);
-            });
-
-    /// <summary>
-    /// Sets a command's handler based on an <see cref="Action{T1,T2,T3,T4}"/>.
-    /// </summary>
-    public static void SetHandler<T1, T2, T3, T4>(
-        this Command command,
-        Action<T1, T2, T3, T4> handle,
-        IValueDescriptor<T1> symbol1,
-        IValueDescriptor<T2> symbol2,
-        IValueDescriptor<T3> symbol3,
-        IValueDescriptor<T4> symbol4) =>
-        command.Handler = new AnonymousCommandHandler(
-            context =>
-            {
-                var value1 = GetValueForHandlerParameter(symbol1, context);
-                var value2 = GetValueForHandlerParameter(symbol2, context);
-                var value3 = GetValueForHandlerParameter(symbol3, context);
-                var value4 = GetValueForHandlerParameter(symbol4, context);
-
-                handle(value1!, value2!, value3!, value4!);
-            });
-
-    /// <summary>
-    /// Sets a command's handler based on an <see cref="Action{T1,T2,T3,T4,T5}"/>.
-    /// </summary>
-    public static void SetHandler<T1, T2, T3, T4, T5>(
-        this Command command,
-        Action<T1, T2, T3, T4, T5> handle,
-        IValueDescriptor<T1> symbol1,
-        IValueDescriptor<T2> symbol2,
-        IValueDescriptor<T3> symbol3,
-        IValueDescriptor<T4> symbol4,
-        IValueDescriptor<T5> symbol5) =>
-        command.Handler = new AnonymousCommandHandler(
-            context =>
-            {
-                var value1 = GetValueForHandlerParameter(symbol1, context);
-                var value2 = GetValueForHandlerParameter(symbol2, context);
-                var value3 = GetValueForHandlerParameter(symbol3, context);
-                var value4 = GetValueForHandlerParameter(symbol4, context);
-                var value5 = GetValueForHandlerParameter(symbol5, context);
-
-                handle(value1!, value2!, value3!, value4!, value5!);
-            });
-
-    /// <summary>
-    /// Sets a command's handler based on an <see cref="Action{T1,T2,T3,T4,T5,T6}"/>.
-    /// </summary>
-    public static void SetHandler<T1, T2, T3, T4, T5, T6>(
-        this Command command,
-        Action<T1, T2, T3, T4, T5, T6> handle,
-        IValueDescriptor<T1> symbol1,
-        IValueDescriptor<T2> symbol2,
-        IValueDescriptor<T3> symbol3,
-        IValueDescriptor<T4> symbol4,
-        IValueDescriptor<T5> symbol5,
-        IValueDescriptor<T6> symbol6) =>
-        command.Handler = new AnonymousCommandHandler(
-            context =>
-            {
-                var value1 = GetValueForHandlerParameter(symbol1, context);
-                var value2 = GetValueForHandlerParameter(symbol2, context);
-                var value3 = GetValueForHandlerParameter(symbol3, context);
-                var value4 = GetValueForHandlerParameter(symbol4, context);
-                var value5 = GetValueForHandlerParameter(symbol5, context);
-                var value6 = GetValueForHandlerParameter(symbol6, context);
-
-                handle(value1!, value2!, value3!, value4!, value5!, value6!);
-            });
-
-    /// <summary>
-    /// Sets a command's handler based on an <see cref="Action{T1,T2,T3,T4,T5,T6,T7}"/>.
-    /// </summary>
-    public static void SetHandler<T1, T2, T3, T4, T5, T6, T7>(
-        this Command command,
-        Action<T1, T2, T3, T4, T5, T6, T7> handle,
-        IValueDescriptor<T1> symbol1,
-        IValueDescriptor<T2> symbol2,
-        IValueDescriptor<T3> symbol3,
-        IValueDescriptor<T4> symbol4,
-        IValueDescriptor<T5> symbol5,
-        IValueDescriptor<T6> symbol6,
-        IValueDescriptor<T7> symbol7) =>
-        command.Handler = new AnonymousCommandHandler(
-            context =>
-            {
-                var value1 = GetValueForHandlerParameter(symbol1, context);
-                var value2 = GetValueForHandlerParameter(symbol2, context);
-                var value3 = GetValueForHandlerParameter(symbol3, context);
-                var value4 = GetValueForHandlerParameter(symbol4, context);
-                var value5 = GetValueForHandlerParameter(symbol5, context);
-                var value6 = GetValueForHandlerParameter(symbol6, context);
-                var value7 = GetValueForHandlerParameter(symbol7, context);
-
-                handle(value1!, value2!, value3!, value4!, value5!, value6!, value7!);
-            });
-
-    /// <summary>
-    /// Sets a command's handler based on an <see cref="Action{T1,T2,T3,T4,T5,T6,T7,T8}"/>.
-    /// </summary>
-    public static void SetHandler<T1, T2, T3, T4, T5, T6, T7, T8>(
-        this Command command,
-        Action<T1, T2, T3, T4, T5, T6, T7, T8> handle,
-        IValueDescriptor<T1> symbol1,
-        IValueDescriptor<T2> symbol2,
-        IValueDescriptor<T3> symbol3,
-        IValueDescriptor<T4> symbol4,
-        IValueDescriptor<T5> symbol5,
-        IValueDescriptor<T6> symbol6,
-        IValueDescriptor<T7> symbol7,
-        IValueDescriptor<T8> symbol8) =>
-        command.Handler = new AnonymousCommandHandler(
-            context =>
-            {
-                var value1 = GetValueForHandlerParameter(symbol1, context);
-                var value2 = GetValueForHandlerParameter(symbol2, context);
-                var value3 = GetValueForHandlerParameter(symbol3, context);
-                var value4 = GetValueForHandlerParameter(symbol4, context);
-                var value5 = GetValueForHandlerParameter(symbol5, context);
-                var value6 = GetValueForHandlerParameter(symbol6, context);
-                var value7 = GetValueForHandlerParameter(symbol7, context);
-                var value8 = GetValueForHandlerParameter(symbol8, context);
-
-                handle(value1!, value2!, value3!, value4!, value5!, value6!, value7!, value8!);
-            });
 }
\ No newline at end of file
diff --git a/src/System.CommandLine/Handler.Func.cs b/src/System.CommandLine/Handler.Func.cs
index b791fecc53..0fd930c8a2 100644
--- a/src/System.CommandLine/Handler.Func.cs
+++ b/src/System.CommandLine/Handler.Func.cs
@@ -1,7 +1,6 @@
 // Copyright (c) .NET Foundation and contributors. All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
-using System.CommandLine.Binding;
 using System.CommandLine.Invocation;
 using System.Threading;
 using System.Threading.Tasks;
@@ -13,14 +12,6 @@ namespace System.CommandLine;
 /// </summary>
 public static partial class Handler
 {
-    /// <summary>
-    /// Sets a command's handler based on a <see cref="Func{Task}"/>.
-    /// </summary>
-    public static void SetHandler(
-        this Command command,
-        Func<CancellationToken, Task> handle) =>
-        command.Handler = new AnonymousCommandHandler((ctx, cancellationToken) => handle(cancellationToken));
-
     /// <summary>
     /// Sets a command's handler based on a <see cref="Func{Task,InvocationContext}"/>.
     /// </summary>
@@ -28,180 +19,4 @@ public static void SetHandler(
         this Command command,
         Func<InvocationContext, CancellationToken, Task> handle) =>
         command.Handler = new AnonymousCommandHandler(handle);
-    
-    /// <summary>
-    /// Sets a command's handler based on a <see cref="Func{T,Task}"/>.
-    /// </summary>
-    public static void SetHandler<T>(
-        this Command command,
-        Func<T, CancellationToken, Task> handle,
-        IValueDescriptor<T> symbol) =>
-        command.Handler = new AnonymousCommandHandler(
-            (context, cancellationToken) =>
-            {
-                var value1 = GetValueForHandlerParameter(symbol, context);
-
-                return handle(value1!, cancellationToken);
-            });
-
-    /// <summary>
-    /// Sets a command's handler based on a <see cref="Func{T1,T2,Task}"/>.
-    /// </summary>
-    public static void SetHandler<T1, T2>(
-        this Command command,
-        Func<T1, T2, CancellationToken, Task> handle,
-        IValueDescriptor<T1> symbol1,
-        IValueDescriptor<T2> symbol2) =>
-        command.Handler = new AnonymousCommandHandler(
-            (context, cancellationToken) =>
-            {
-                var value1 = GetValueForHandlerParameter(symbol1, context);
-                var value2 = GetValueForHandlerParameter(symbol2, context);
-
-                return handle(value1!, value2!, cancellationToken);
-            });
-
-    /// <summary>
-    /// Sets a command's handler based on a <see cref="Func{T1,T2,T3,Task}"/>.
-    /// </summary>
-    public static void SetHandler<T1, T2, T3>(
-        this Command command,
-        Func<T1, T2, T3, CancellationToken, Task> handle,
-        IValueDescriptor<T1> symbol1,
-        IValueDescriptor<T2> symbol2,
-        IValueDescriptor<T3> symbol3) =>
-        command.Handler = new AnonymousCommandHandler(
-            (context, cancellationToken) =>
-            {
-                var value1 = GetValueForHandlerParameter(symbol1, context);
-                var value2 = GetValueForHandlerParameter(symbol2, context);
-                var value3 = GetValueForHandlerParameter(symbol3, context);
-
-                return handle(value1!, value2!, value3!, cancellationToken);
-            });
-
-    /// <summary>
-    /// Sets a command's handler based on a <see cref="Func{T1,T2,T3,T4,Task}"/>.
-    /// </summary>
-    public static void SetHandler<T1, T2, T3, T4>(
-        this Command command,
-        Func<T1, T2, T3, T4, CancellationToken, Task> handle,
-        IValueDescriptor<T1> symbol1,
-        IValueDescriptor<T2> symbol2,
-        IValueDescriptor<T3> symbol3,
-        IValueDescriptor<T4> symbol4) =>
-        command.Handler = new AnonymousCommandHandler(
-            (context, cancellationToken) =>
-            {
-                var value1 = GetValueForHandlerParameter(symbol1, context);
-                var value2 = GetValueForHandlerParameter(symbol2, context);
-                var value3 = GetValueForHandlerParameter(symbol3, context);
-                var value4 = GetValueForHandlerParameter(symbol4, context);
-
-                return handle(value1!, value2!, value3!, value4!, cancellationToken);
-            });
-
-    /// <summary>
-    /// Sets a command's handler based on a <see cref="Func{T1,T2,T3,T4,T5,Task}"/>.
-    /// </summary>
-    public static void SetHandler<T1, T2, T3, T4, T5>(
-        this Command command,
-        Func<T1, T2, T3, T4, T5, CancellationToken, Task> handle,
-        IValueDescriptor<T1> symbol1,
-        IValueDescriptor<T2> symbol2,
-        IValueDescriptor<T3> symbol3,
-        IValueDescriptor<T4> symbol4,
-        IValueDescriptor<T5> symbol5) =>
-        command.Handler = new AnonymousCommandHandler(
-            (context, cancellationToken) =>
-            {
-                var value1 = GetValueForHandlerParameter(symbol1, context);
-                var value2 = GetValueForHandlerParameter(symbol2, context);
-                var value3 = GetValueForHandlerParameter(symbol3, context);
-                var value4 = GetValueForHandlerParameter(symbol4, context);
-                var value5 = GetValueForHandlerParameter(symbol5, context);
-
-                return handle(value1!, value2!, value3!, value4!, value5!, cancellationToken);
-            });
-
-    /// <summary>
-    /// Sets a command's handler based on a <see cref="Func{T1,T2,T3,T4,T5,T6,Task}"/>.
-    /// </summary>
-    public static void SetHandler<T1, T2, T3, T4, T5, T6>(
-        this Command command,
-        Func<T1, T2, T3, T4, T5, T6, CancellationToken, Task> handle,
-        IValueDescriptor<T1> symbol1,
-        IValueDescriptor<T2> symbol2,
-        IValueDescriptor<T3> symbol3,
-        IValueDescriptor<T4> symbol4,
-        IValueDescriptor<T5> symbol5,
-        IValueDescriptor<T6> symbol6) =>
-        command.Handler = new AnonymousCommandHandler(
-            (context, cancellationToken) =>
-            {
-                var value1 = GetValueForHandlerParameter(symbol1, context);
-                var value2 = GetValueForHandlerParameter(symbol2, context);
-                var value3 = GetValueForHandlerParameter(symbol3, context);
-                var value4 = GetValueForHandlerParameter(symbol4, context);
-                var value5 = GetValueForHandlerParameter(symbol5, context);
-                var value6 = GetValueForHandlerParameter(symbol6, context);
-
-                return handle(value1!, value2!, value3!, value4!, value5!, value6!, cancellationToken);
-            });
-
-    /// <summary>
-    /// Sets a command's handler based on a <see cref="Func{T1,T2,T3,T4,T5,T6,T7,Task}"/>.
-    /// </summary>
-    public static void SetHandler<T1, T2, T3, T4, T5, T6, T7>(
-        this Command command,
-        Func<T1, T2, T3, T4, T5, T6, T7, CancellationToken, Task> handle,
-        IValueDescriptor<T1> symbol1,
-        IValueDescriptor<T2> symbol2,
-        IValueDescriptor<T3> symbol3,
-        IValueDescriptor<T4> symbol4,
-        IValueDescriptor<T5> symbol5,
-        IValueDescriptor<T6> symbol6,
-        IValueDescriptor<T7> symbol7) =>
-        command.Handler = new AnonymousCommandHandler(
-            (context, cancellationToken) =>
-            {
-                var value1 = GetValueForHandlerParameter(symbol1, context);
-                var value2 = GetValueForHandlerParameter(symbol2, context);
-                var value3 = GetValueForHandlerParameter(symbol3, context);
-                var value4 = GetValueForHandlerParameter(symbol4, context);
-                var value5 = GetValueForHandlerParameter(symbol5, context);
-                var value6 = GetValueForHandlerParameter(symbol6, context);
-                var value7 = GetValueForHandlerParameter(symbol7, context);
-
-                return handle(value1!, value2!, value3!, value4!, value5!, value6!, value7!, cancellationToken);
-            });
-
-    /// <summary>
-    /// Sets a command's handler based on a <see cref="Func{T1,T2,T3,T4,T5,T6,T7,T8,Task}"/>.
-    /// </summary>
-    public static void SetHandler<T1, T2, T3, T4, T5, T6, T7, T8>(
-        this Command command,
-        Func<T1, T2, T3, T4, T5, T6, T7, T8, CancellationToken, Task> handle,
-        IValueDescriptor<T1> symbol1,
-        IValueDescriptor<T2> symbol2,
-        IValueDescriptor<T3> symbol3,
-        IValueDescriptor<T4> symbol4,
-        IValueDescriptor<T5> symbol5,
-        IValueDescriptor<T6> symbol6,
-        IValueDescriptor<T7> symbol7,
-        IValueDescriptor<T8> symbol8) =>
-        command.Handler = new AnonymousCommandHandler(
-            (context, cancellationToken) =>
-            {
-                var value1 = GetValueForHandlerParameter(symbol1, context);
-                var value2 = GetValueForHandlerParameter(symbol2, context);
-                var value3 = GetValueForHandlerParameter(symbol3, context);
-                var value4 = GetValueForHandlerParameter(symbol4, context);
-                var value5 = GetValueForHandlerParameter(symbol5, context);
-                var value6 = GetValueForHandlerParameter(symbol6, context);
-                var value7 = GetValueForHandlerParameter(symbol7, context);
-                var value8 = GetValueForHandlerParameter(symbol8, context);
-
-                return handle(value1!, value2!, value3!, value4!, value5!, value6!, value7!, value8!, cancellationToken);
-            });
 }
\ No newline at end of file
diff --git a/src/System.CommandLine/Handler.cs b/src/System.CommandLine/Handler.cs
deleted file mode 100644
index a60a41d361..0000000000
--- a/src/System.CommandLine/Handler.cs
+++ /dev/null
@@ -1,26 +0,0 @@
-// Copyright (c) .NET Foundation and contributors. All rights reserved.
-// Licensed under the MIT license. See LICENSE file in the project root for full license information.
-
-using System.CommandLine.Binding;
-using System.CommandLine.Invocation;
-
-namespace System.CommandLine;
-
-public static partial class Handler
-{
-    private static T? GetValueForHandlerParameter<T>(
-        IValueDescriptor<T> symbol,
-        InvocationContext context)
-    {
-        if (symbol is IValueSource valueSource &&
-            valueSource.TryGetValue(symbol, context.BindingContext, out var boundValue) &&
-            boundValue is T value)
-        {
-            return value;
-        }
-        else
-        {
-            return context.ParseResult.GetValueFor(symbol);
-        }
-    }
-}
\ No newline at end of file

From a34ed2dd6457c72701c13b597760515129062d63 Mon Sep 17 00:00:00 2001
From: Adam Sitnik <adam.sitnik@gmail.com>
Date: Mon, 13 Mar 2023 15:49:13 +0100
Subject: [PATCH 2/5] merge Command.SetHandler extension methods into Command

---
 ...ommandLine_api_is_not_changed.approved.txt |  5 ++---
 src/System.CommandLine/Command.cs             | 17 +++++++++++++-
 src/System.CommandLine/Handler.Action.cs      | 20 -----------------
 src/System.CommandLine/Handler.Func.cs        | 22 -------------------
 4 files changed, 18 insertions(+), 46 deletions(-)
 delete mode 100644 src/System.CommandLine/Handler.Action.cs
 delete mode 100644 src/System.CommandLine/Handler.Func.cs

diff --git a/src/System.CommandLine.ApiCompatibility.Tests/ApiCompatibilityApprovalTests.System_CommandLine_api_is_not_changed.approved.txt b/src/System.CommandLine.ApiCompatibility.Tests/ApiCompatibilityApprovalTests.System_CommandLine_api_is_not_changed.approved.txt
index abc07ddebf..aefba634a5 100644
--- a/src/System.CommandLine.ApiCompatibility.Tests/ApiCompatibilityApprovalTests.System_CommandLine_api_is_not_changed.approved.txt
+++ b/src/System.CommandLine.ApiCompatibility.Tests/ApiCompatibilityApprovalTests.System_CommandLine_api_is_not_changed.approved.txt
@@ -50,6 +50,8 @@ System.CommandLine
     public System.Collections.Generic.IEnumerator<Symbol> GetEnumerator()
     public ParseResult Parse(System.Collections.Generic.IReadOnlyList<System.String> args, CommandLineConfiguration configuration = null)
     public ParseResult Parse(System.String commandLine, CommandLineConfiguration configuration = null)
+    public System.Void SetHandler(System.Action<System.CommandLine.Invocation.InvocationContext> handle)
+    public System.Void SetHandler(System.Func<System.CommandLine.Invocation.InvocationContext,System.Threading.CancellationToken,System.Threading.Tasks.Task> handle)
   public static class CommandExtensions
     public static System.Int32 Invoke(this Command command, System.String[] args, IConsole console = null)
     public static System.Int32 Invoke(this Command command, System.String commandLine, IConsole console = null)
@@ -108,9 +110,6 @@ System.CommandLine
     public System.Void SetSynchronousHandler(System.Action<System.CommandLine.Invocation.InvocationContext> handler)
   public class EnvironmentVariablesDirective : Directive
     .ctor()
-  public static class Handler
-    public static System.Void SetHandler(this Command command, System.Action<System.CommandLine.Invocation.InvocationContext> handle)
-    public static System.Void SetHandler(this Command command, System.Func<System.CommandLine.Invocation.InvocationContext,System.Threading.CancellationToken,System.Threading.Tasks.Task> handle)
   public interface ICommandHandler
     public System.Int32 Invoke(System.CommandLine.Invocation.InvocationContext context)
     public System.Threading.Tasks.Task<System.Int32> InvokeAsync(System.CommandLine.Invocation.InvocationContext context, System.Threading.CancellationToken cancellationToken = null)
diff --git a/src/System.CommandLine/Command.cs b/src/System.CommandLine/Command.cs
index 753d5938c1..c0d43bd14e 100644
--- a/src/System.CommandLine/Command.cs
+++ b/src/System.CommandLine/Command.cs
@@ -4,9 +4,12 @@
 using System.Collections;
 using System.Collections.Generic;
 using System.CommandLine.Completions;
+using System.CommandLine.Invocation;
 using System.CommandLine.Parsing;
 using System.ComponentModel;
 using System.Linq;
+using System.Threading.Tasks;
+using System.Threading;
 
 namespace System.CommandLine
 {
@@ -123,7 +126,7 @@ public void Add(Symbol symbol)
         /// that will be performed when the command is invoked.
         /// </summary>
         /// <remarks>
-        /// <para>Use one of the <see cref="Handler.SetHandler(Command, Action)" /> overloads to construct a handler.</para>
+        /// <para>Use one of the <see cref="SetHandler(Action{InvocationContext})" /> overloads to construct a handler.</para>
         /// <para>If the handler is not specified, parser errors will be generated for command line input that
         /// invokes this command.</para></remarks>
         public ICommandHandler? Handler { get; set; }
@@ -251,6 +254,18 @@ void AddCompletionsFor(Symbol identifier, AliasSet? aliases)
             }
         }
 
+        /// <summary>
+        /// Sets a command's handler based on an <see cref="Action{InvocationContext}"/>.
+        /// </summary>
+        public void SetHandler(Action<InvocationContext> handle)
+            => Handler = new AnonymousCommandHandler(handle);
+
+        /// <summary>
+        /// Sets a command's handler based on a <see cref="Func{Task,InvocationContext}"/>.
+        /// </summary>
+        public void SetHandler(Func<InvocationContext, CancellationToken, Task> handle)
+            => Handler = new AnonymousCommandHandler(handle);
+
         internal bool EqualsNameOrAlias(string name)
             => Name.Equals(name, StringComparison.Ordinal) || (_aliases is not null && _aliases.Contains(name));
     }
diff --git a/src/System.CommandLine/Handler.Action.cs b/src/System.CommandLine/Handler.Action.cs
deleted file mode 100644
index 2812339f3f..0000000000
--- a/src/System.CommandLine/Handler.Action.cs
+++ /dev/null
@@ -1,20 +0,0 @@
-// Copyright (c) .NET Foundation and contributors. All rights reserved.
-// Licensed under the MIT license. See LICENSE file in the project root for full license information.
-
-using System.CommandLine.Invocation;
-
-namespace System.CommandLine;
-
-/// <summary>
-/// Provides methods for creating and working with command handlers.
-/// </summary>
-public static partial class Handler
-{
-    /// <summary>
-    /// Sets a command's handler based on an <see cref="Action{InvocationContext}"/>.
-    /// </summary>
-    public static void SetHandler(
-        this Command command,
-        Action<InvocationContext> handle) =>
-        command.Handler = new AnonymousCommandHandler(handle);
-}
\ No newline at end of file
diff --git a/src/System.CommandLine/Handler.Func.cs b/src/System.CommandLine/Handler.Func.cs
deleted file mode 100644
index 0fd930c8a2..0000000000
--- a/src/System.CommandLine/Handler.Func.cs
+++ /dev/null
@@ -1,22 +0,0 @@
-// Copyright (c) .NET Foundation and contributors. All rights reserved.
-// Licensed under the MIT license. See LICENSE file in the project root for full license information.
-
-using System.CommandLine.Invocation;
-using System.Threading;
-using System.Threading.Tasks;
-
-namespace System.CommandLine;
-
-/// <summary>
-/// Provides methods for creating and working with command handlers.
-/// </summary>
-public static partial class Handler
-{
-    /// <summary>
-    /// Sets a command's handler based on a <see cref="Func{Task,InvocationContext}"/>.
-    /// </summary>
-    public static void SetHandler(
-        this Command command,
-        Func<InvocationContext, CancellationToken, Task> handle) =>
-        command.Handler = new AnonymousCommandHandler(handle);
-}
\ No newline at end of file

From 2bb2102a784ef15bdbc005fae20334a4e2ad3f96 Mon Sep 17 00:00:00 2001
From: Adam Sitnik <adam.sitnik@gmail.com>
Date: Mon, 13 Mar 2023 16:03:02 +0100
Subject: [PATCH 3/5] remove IValueDescriptor<T>

---
 ....System_CommandLine_api_is_not_changed.approved.txt |  7 +++----
 src/System.CommandLine/Argument{T}.cs                  |  3 +--
 src/System.CommandLine/Binding/BinderBase{T}.cs        |  2 +-
 src/System.CommandLine/Binding/IValueDescriptor{T}.cs  | 10 ----------
 src/System.CommandLine/Option{T}.cs                    |  3 +--
 src/System.CommandLine/ParseResult.cs                  |  8 --------
 6 files changed, 6 insertions(+), 27 deletions(-)
 delete mode 100644 src/System.CommandLine/Binding/IValueDescriptor{T}.cs

diff --git a/src/System.CommandLine.ApiCompatibility.Tests/ApiCompatibilityApprovalTests.System_CommandLine_api_is_not_changed.approved.txt b/src/System.CommandLine.ApiCompatibility.Tests/ApiCompatibilityApprovalTests.System_CommandLine_api_is_not_changed.approved.txt
index aefba634a5..a4596a15f2 100644
--- a/src/System.CommandLine.ApiCompatibility.Tests/ApiCompatibilityApprovalTests.System_CommandLine_api_is_not_changed.approved.txt
+++ b/src/System.CommandLine.ApiCompatibility.Tests/ApiCompatibilityApprovalTests.System_CommandLine_api_is_not_changed.approved.txt
@@ -9,7 +9,7 @@ System.CommandLine
     public System.Collections.Generic.IEnumerable<System.CommandLine.Completions.CompletionItem> GetCompletions(System.CommandLine.Completions.CompletionContext context)
     public System.Object GetDefaultValue()
     public System.String ToString()
-  public class Argument<T> : Argument, IValueDescriptor<T>, System.CommandLine.Binding.IValueDescriptor
+  public class Argument<T> : Argument, System.CommandLine.Binding.IValueDescriptor
     .ctor(System.String name)
     public Func<System.CommandLine.Parsing.ArgumentResult,T> CustomParser { get; set; }
     public Func<System.CommandLine.Parsing.ArgumentResult,T> DefaultValueFactory { get; set; }
@@ -125,7 +125,7 @@ System.CommandLine
     public System.Collections.Generic.List<System.Action<System.CommandLine.Parsing.OptionResult>> Validators { get; }
     public System.Type ValueType { get; }
     public System.Collections.Generic.IEnumerable<System.CommandLine.Completions.CompletionItem> GetCompletions(System.CommandLine.Completions.CompletionContext context)
-  public class Option<T> : Option, IValueDescriptor<T>, System.CommandLine.Binding.IValueDescriptor
+  public class Option<T> : Option, System.CommandLine.Binding.IValueDescriptor
     .ctor(System.String name, System.String[] aliases)
     public Func<System.CommandLine.Parsing.ArgumentResult,T> CustomParser { get; set; }
     public Func<System.CommandLine.Parsing.ArgumentResult,T> DefaultValueFactory { get; set; }
@@ -172,7 +172,7 @@ System.CommandLine
     public System.Collections.Generic.IEnumerable<System.CommandLine.Completions.CompletionItem> GetCompletions(System.CommandLine.Completions.CompletionContext context)
     public System.String ToString()
 System.CommandLine.Binding
-  public abstract class BinderBase<T>, IValueDescriptor<T>, IValueDescriptor, IValueSource
+  public abstract class BinderBase<T>, IValueDescriptor, IValueSource
     protected T GetBoundValue(BindingContext bindingContext)
   public class BindingContext, System.IServiceProvider
     public System.CommandLine.IConsole Console { get; }
@@ -190,7 +190,6 @@ System.CommandLine.Binding
     public System.String ValueName { get; }
     public System.Type ValueType { get; }
     public System.Object GetDefaultValue()
-  public interface IValueDescriptor<out T> : IValueDescriptor
   public interface IValueSource
     public System.Boolean TryGetValue(IValueDescriptor valueDescriptor, BindingContext bindingContext, ref System.Object& boundValue)
 System.CommandLine.Completions
diff --git a/src/System.CommandLine/Argument{T}.cs b/src/System.CommandLine/Argument{T}.cs
index dc10e5331e..324e5e5091 100644
--- a/src/System.CommandLine/Argument{T}.cs
+++ b/src/System.CommandLine/Argument{T}.cs
@@ -1,14 +1,13 @@
 // Copyright (c) .NET Foundation and contributors. All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
-using System.CommandLine.Binding;
 using System.CommandLine.Parsing;
 using System.IO;
 
 namespace System.CommandLine
 {
     /// <inheritdoc cref="Argument" />
-    public class Argument<T> : Argument, IValueDescriptor<T>
+    public class Argument<T> : Argument
     {
         private Func<ArgumentResult, T>? _customParser;
 
diff --git a/src/System.CommandLine/Binding/BinderBase{T}.cs b/src/System.CommandLine/Binding/BinderBase{T}.cs
index 94f034acd3..40f6cdac3e 100644
--- a/src/System.CommandLine/Binding/BinderBase{T}.cs
+++ b/src/System.CommandLine/Binding/BinderBase{T}.cs
@@ -5,7 +5,7 @@
 /// </summary>
 /// <typeparam name="T">The type to be bound.</typeparam>
 public abstract class BinderBase<T> :
-    IValueDescriptor<T>,
+    IValueDescriptor,
     IValueSource
 {
     /// <summary>
diff --git a/src/System.CommandLine/Binding/IValueDescriptor{T}.cs b/src/System.CommandLine/Binding/IValueDescriptor{T}.cs
deleted file mode 100644
index 1c68dc078f..0000000000
--- a/src/System.CommandLine/Binding/IValueDescriptor{T}.cs
+++ /dev/null
@@ -1,10 +0,0 @@
-// Copyright (c) .NET Foundation and contributors. All rights reserved.
-// Licensed under the MIT license. See LICENSE file in the project root for full license information.
-
-namespace System.CommandLine.Binding
-{
-    /// <inheritdoc />
-    public interface IValueDescriptor<out T> : IValueDescriptor
-    {
-    }
-}
\ No newline at end of file
diff --git a/src/System.CommandLine/Option{T}.cs b/src/System.CommandLine/Option{T}.cs
index 5a7ae32fee..99f3325fbd 100644
--- a/src/System.CommandLine/Option{T}.cs
+++ b/src/System.CommandLine/Option{T}.cs
@@ -1,14 +1,13 @@
 // Copyright (c) .NET Foundation and contributors. All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
-using System.CommandLine.Binding;
 using System.CommandLine.Parsing;
 
 namespace System.CommandLine
 {
     /// <inheritdoc cref="Option" />
     /// <typeparam name="T">The <see cref="System.Type"/> that the option's arguments are expected to be parsed as.</typeparam>
-    public class Option<T> : Option, IValueDescriptor<T>
+    public class Option<T> : Option
     {
         internal readonly Argument<T> _argument;
 
diff --git a/src/System.CommandLine/ParseResult.cs b/src/System.CommandLine/ParseResult.cs
index 1c9ec067a8..b8ccaed431 100644
--- a/src/System.CommandLine/ParseResult.cs
+++ b/src/System.CommandLine/ParseResult.cs
@@ -105,14 +105,6 @@ CommandLineText is null
                     ? new TokenCompletionContext(this)
                     : new TextCompletionContext(this, CommandLineText);
 
-        internal T? GetValueFor<T>(IValueDescriptor<T> symbol) =>
-            symbol switch
-            {
-                Argument<T> argument => GetValue(argument),
-                Option<T> option => GetValue(option),
-                _ => throw new ArgumentOutOfRangeException()
-            };
-
         /// <summary>
         /// Gets the parsed or default value for the specified argument.
         /// </summary>

From c64bc509e481934b495cff2d20dcd891b3603a2b Mon Sep 17 00:00:00 2001
From: Adam Sitnik <adam.sitnik@gmail.com>
Date: Mon, 13 Mar 2023 16:43:00 +0100
Subject: [PATCH 4/5] remove BinderBase<T>

---
 ...ommandLine_api_is_not_changed.approved.txt |  2 --
 .../Binding/SetHandlerTests.cs                | 31 -------------------
 .../Binding/BinderBase{T}.cs                  | 31 -------------------
 3 files changed, 64 deletions(-)
 delete mode 100644 src/System.CommandLine/Binding/BinderBase{T}.cs

diff --git a/src/System.CommandLine.ApiCompatibility.Tests/ApiCompatibilityApprovalTests.System_CommandLine_api_is_not_changed.approved.txt b/src/System.CommandLine.ApiCompatibility.Tests/ApiCompatibilityApprovalTests.System_CommandLine_api_is_not_changed.approved.txt
index a4596a15f2..f48fa8eeb6 100644
--- a/src/System.CommandLine.ApiCompatibility.Tests/ApiCompatibilityApprovalTests.System_CommandLine_api_is_not_changed.approved.txt
+++ b/src/System.CommandLine.ApiCompatibility.Tests/ApiCompatibilityApprovalTests.System_CommandLine_api_is_not_changed.approved.txt
@@ -172,8 +172,6 @@ System.CommandLine
     public System.Collections.Generic.IEnumerable<System.CommandLine.Completions.CompletionItem> GetCompletions(System.CommandLine.Completions.CompletionContext context)
     public System.String ToString()
 System.CommandLine.Binding
-  public abstract class BinderBase<T>, IValueDescriptor, IValueSource
-    protected T GetBoundValue(BindingContext bindingContext)
   public class BindingContext, System.IServiceProvider
     public System.CommandLine.IConsole Console { get; }
     public System.CommandLine.ParseResult ParseResult { get; }
diff --git a/src/System.CommandLine.Tests/Binding/SetHandlerTests.cs b/src/System.CommandLine.Tests/Binding/SetHandlerTests.cs
index 9b0dc3a409..ed9ef18e5a 100644
--- a/src/System.CommandLine.Tests/Binding/SetHandlerTests.cs
+++ b/src/System.CommandLine.Tests/Binding/SetHandlerTests.cs
@@ -16,37 +16,6 @@ namespace System.CommandLine.Tests.Binding
 {
     public class SetHandlerTests
     {
-        public class CustomType
-        {
-            public string StringValue { get; set; }
-
-            public int IntValue { get; set; }
-
-            public IConsole Console { get; set; }
-        }
-
-        public class CustomBinder : BinderBase<CustomType>
-        {
-            private readonly Option<int> _intOption;
-            private readonly Argument<string> _stringArg;
-
-            public CustomBinder(Option<int> intOption, Argument<string> stringArg)
-            {
-                _intOption = intOption;
-                _stringArg = stringArg;
-            }
-
-            protected override CustomType GetBoundValue(BindingContext bindingContext)
-            {
-                return new CustomType
-                {
-                    Console = bindingContext.Console,
-                    IntValue = bindingContext.ParseResult.GetValue(_intOption),
-                    StringValue = bindingContext.ParseResult.GetValue(_stringArg),
-                };
-            }
-        }
-
         [Fact]
         public async Task Unexpected_return_types_result_in_exit_code_0_if_no_exception_was_thrown()
         {
diff --git a/src/System.CommandLine/Binding/BinderBase{T}.cs b/src/System.CommandLine/Binding/BinderBase{T}.cs
deleted file mode 100644
index 40f6cdac3e..0000000000
--- a/src/System.CommandLine/Binding/BinderBase{T}.cs
+++ /dev/null
@@ -1,31 +0,0 @@
-namespace System.CommandLine.Binding;
-
-/// <summary>
-/// Supports binding of custom types.
-/// </summary>
-/// <typeparam name="T">The type to be bound.</typeparam>
-public abstract class BinderBase<T> :
-    IValueDescriptor,
-    IValueSource
-{
-    /// <summary>
-    /// Gets a value from the binding context.
-    /// </summary>
-    /// <param name="bindingContext"></param>
-    /// <returns></returns>
-    protected abstract T GetBoundValue(BindingContext bindingContext);
-
-    string IValueDescriptor.ValueName => GetType().Name;
-
-    Type IValueDescriptor.ValueType => typeof(T);
-
-    bool IValueDescriptor.HasDefaultValue => false;
-
-    object? IValueDescriptor.GetDefaultValue() => default(T);
-
-    bool IValueSource.TryGetValue(IValueDescriptor valueDescriptor, BindingContext bindingContext, out object? boundValue)
-    {
-        boundValue = GetBoundValue(bindingContext);
-        return true;
-    }
-}
\ No newline at end of file

From e3406008d048c254bbc5ec1db1c5329bb2607214 Mon Sep 17 00:00:00 2001
From: Adam Sitnik <adam.sitnik@gmail.com>
Date: Mon, 13 Mar 2023 18:34:42 +0100
Subject: [PATCH 5/5] address code review feedback: fix the comment

---
 src/System.CommandLine/Command.cs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/System.CommandLine/Command.cs b/src/System.CommandLine/Command.cs
index c0d43bd14e..e95b9af290 100644
--- a/src/System.CommandLine/Command.cs
+++ b/src/System.CommandLine/Command.cs
@@ -261,7 +261,7 @@ public void SetHandler(Action<InvocationContext> handle)
             => Handler = new AnonymousCommandHandler(handle);
 
         /// <summary>
-        /// Sets a command's handler based on a <see cref="Func{Task,InvocationContext}"/>.
+        /// Sets a command's handler based on a <see cref="Func{InvocationContext,CancellationToken,Task}"/>.
         /// </summary>
         public void SetHandler(Func<InvocationContext, CancellationToken, Task> handle)
             => Handler = new AnonymousCommandHandler(handle);