A Programmer with Microsoft tools

RSCG – jab

name	jab
nuget	https://www.nuget.org/packages/jab/
link	https://github.com/pakrym/jab
author	Pavel Krymets

generating DI code

This is how you can use jab .

The code that you start with is


<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net8.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
  </PropertyGroup>
	<ItemGroup>
		<PackageReference Include="Jab" Version="0.10.2" PrivateAssets="all" />
	</ItemGroup>
	<PropertyGroup>
		<EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
		<CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath>
	</PropertyGroup>
</Project>

The code that you will use is


using InjectDemo;
using Jab;
MyServiceProvider sc = new();
//var con = sc.GetService<DatabaseCon>();
var db = sc.GetService<IDatabase>();
db.Open();


[ServiceProvider]
//[Transient(typeof(DatabaseCon), typeof(DatabaseCon))]
[Transient(typeof(IDatabase), typeof(DatabaseCon))]
internal partial class MyServiceProvider { }


namespace InjectDemo;

internal class Database : IDatabase
{
    private readonly DatabaseCon con;

    public Database(DatabaseCon con)
    {
        this.con = con;
    }
    public void Open()
    {
        Console.WriteLine($"open {con.Connection}");
    }

}



namespace InjectDemo;

internal class DatabaseCon: IDatabase
{
    public string? Connection { get; set; }
    public void Open()
    {
        Console.WriteLine("open" + Connection);
    }
}

The code that is generated is

// <auto-generated/>

#if !JAB_ATTRIBUTES_REFERENCED || JAB_ATTRIBUTES_PACKAGE

using System;
using System.Threading.Tasks;

#nullable enable

namespace Jab
{
    [AttributeUsage(AttributeTargets.Class, AllowMultiple = false, Inherited = true)]
#if JAB_ATTRIBUTES_PACKAGE
    public
#else
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Jab", null)]
    internal
#endif
    class ServiceProviderAttribute: Attribute
    {
        public Type[]? RootServices { get; set; }
    }

    [AttributeUsage(AttributeTargets.Interface, AllowMultiple = false, Inherited = true)]
#if JAB_ATTRIBUTES_PACKAGE
    public
#else
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Jab", null)]
    internal
#endif
    class ServiceProviderModuleAttribute: Attribute
    {
    }

    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Interface, AllowMultiple = true, Inherited = true)]
#if JAB_ATTRIBUTES_PACKAGE
    public
#else
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Jab", null)]
    internal
#endif
    class ImportAttribute: Attribute
    {
        public Type ModuleType { get; }

        public ImportAttribute(Type moduleType)
        {
            ModuleType = moduleType;
        }
    }

    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Interface, AllowMultiple = true, Inherited = true)]
#if JAB_ATTRIBUTES_PACKAGE
    public
#else
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Jab", null)]
    internal
#endif
    class SingletonAttribute: Attribute
    {
        public Type ServiceType { get; }

        public string? Name { get; set; }

        public Type? ImplementationType { get; }

        public string? Instance { get; set; }

        public string? Factory { get; set; }

        public SingletonAttribute(Type serviceType)
        {
            ServiceType = serviceType;
        }

        public SingletonAttribute(Type serviceType, Type implementationType)
        {
            ServiceType = serviceType;
            ImplementationType = implementationType;
        }
    }

    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Interface, AllowMultiple = true, Inherited = true)]
#if JAB_ATTRIBUTES_PACKAGE
    public
#else
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Jab", null)]
    internal
#endif
    class TransientAttribute : Attribute
    {
        public Type ServiceType { get; }
        public string? Name { get; set; }

        public Type? ImplementationType { get; }

        public string? Factory { get; set; }

        public TransientAttribute(Type serviceType)
        {
            ServiceType = serviceType;
        }

        public TransientAttribute(Type serviceType, Type implementationType)
        {
            ServiceType = serviceType;
            ImplementationType = implementationType;
        }
    }

    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Interface, AllowMultiple = true, Inherited = true)]
#if JAB_ATTRIBUTES_PACKAGE
    public
#else
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Jab", null)]
    internal
#endif
    class ScopedAttribute : Attribute
    {
        public Type ServiceType { get; }
        public string? Name { get; set; }

        public Type? ImplementationType { get; }

        public string? Factory { get; set; }

        public ScopedAttribute(Type serviceType)
        {
            ServiceType = serviceType;
        }

        public ScopedAttribute(Type serviceType, Type implementationType)
        {
            ServiceType = serviceType;
            ImplementationType = implementationType;
        }
    }


    [AttributeUsage(AttributeTargets.Parameter, AllowMultiple = false, Inherited = true)]
#if JAB_ATTRIBUTES_PACKAGE
    public
#else
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Jab", null)]
    internal
#endif
        class FromNamedServicesAttribute : Attribute
    {
        public string? Name { get; set; }

        public FromNamedServicesAttribute(string name)
        {
            Name = name;
        }
    }

#if GENERIC_ATTRIBUTES
    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Interface, AllowMultiple = true, Inherited = true)]
#if JAB_ATTRIBUTES_PACKAGE
    public
#else
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Jab", null)]
    internal
#endif
    class ImportAttribute<TModule> : ImportAttribute
    {
        public ImportAttribute() : base(typeof(TModule))
        {
        }
    }

    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Interface, AllowMultiple = true, Inherited = true)]
#if JAB_ATTRIBUTES_PACKAGE
    public
#else
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Jab", null)]
    internal
#endif
    class TransientAttribute<TService> : TransientAttribute
    {
        public TransientAttribute() : base(typeof(TService))
        {
        }
    }

    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Interface, AllowMultiple = true, Inherited = true)]
#if JAB_ATTRIBUTES_PACKAGE
    public
#else
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Jab", null)]
    internal
#endif
    class TransientAttribute<TService, TImpl> : TransientAttribute where TImpl: TService
    {
        public TransientAttribute() : base(typeof(TService), typeof(TImpl))
        {
        }
    }

    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Interface, AllowMultiple = true, Inherited = true)]
#if JAB_ATTRIBUTES_PACKAGE
    public
#else
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Jab", null)]
    internal
#endif
    class ScopedAttribute<TService> : ScopedAttribute
    {
        public ScopedAttribute() : base(typeof(TService))
        {
        }
    }

    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Interface, AllowMultiple = true, Inherited = true)]
#if JAB_ATTRIBUTES_PACKAGE
    public
#else
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Jab", null)]
    internal
#endif
    class ScopedAttribute<TService, TImpl> : ScopedAttribute where TImpl: TService
    {
        public ScopedAttribute() : base(typeof(TService), typeof(TImpl))
        {
        }
    }


    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Interface, AllowMultiple = true, Inherited = true)]
#if JAB_ATTRIBUTES_PACKAGE
    public
#else
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Jab", null)]
    internal
#endif
    class SingletonAttribute<TService> : SingletonAttribute
    {
        public SingletonAttribute() : base(typeof(TService))
        {
        }
    }

    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Interface, AllowMultiple = true, Inherited = true)]
#if JAB_ATTRIBUTES_PACKAGE
    public
#else
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Jab", null)]
    internal
#endif
    class SingletonAttribute<TService, TImpl> : SingletonAttribute where TImpl: TService
    {
        public SingletonAttribute() : base(typeof(TService), typeof(TImpl))
        {
        }
    }

#endif

#if JAB_ATTRIBUTES_PACKAGE
    public
#else
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Jab", null)]
    internal
#endif
    interface IServiceProvider<T>
    {
        T GetService();
    }

#if JAB_ATTRIBUTES_PACKAGE
    public
#else
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Jab", null)]
    internal
#endif
    interface INamedServiceProvider<T>
    {
        T GetService(string name);
    }

#if JAB_ATTRIBUTES_PACKAGE
    public
#else
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Jab", null)]
    internal
#endif
    static class JabHelpers
    {
        public static InvalidOperationException CreateServiceNotFoundException<T>(string? name = null) =>
            CreateServiceNotFoundException(typeof(T), name);
        public static InvalidOperationException CreateServiceNotFoundException(Type type, string? name = null) =>
            new InvalidOperationException(
                name != null ?
                    $"Service with type {type} and name {name} not registered" :
                    $"Service with type {type} not registered");
    }
}

#endif

// <auto-generated/>

#nullable enable

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Diagnostics.CodeAnalysis;
using System.Threading.Tasks;
using Jab;

using static Jab.JabHelpers;
[global::System.CodeDom.Compiler.GeneratedCodeAttribute("Jab", "0.10.2.0")]
internal partial class MyServiceProvider : global::System.IDisposable,
   System.IAsyncDisposable,
   global::System.IServiceProvider,
   IServiceProvider<InjectDemo.DatabaseCon>,
   IServiceProvider<InjectDemo.IDatabase>,
   IServiceProvider<System.IServiceProvider>
{
    private Scope? _rootScope;
    
    InjectDemo.DatabaseCon IServiceProvider<InjectDemo.DatabaseCon>.GetService()
    {
        InjectDemo.DatabaseCon service = new InjectDemo.DatabaseCon();
        TryAddDisposable(service);
        return service;
    }
    
    InjectDemo.IDatabase IServiceProvider<InjectDemo.IDatabase>.GetService()
    {
        InjectDemo.DatabaseCon service = new InjectDemo.DatabaseCon();
        TryAddDisposable(service);
        return service;
    }
    
    System.IServiceProvider IServiceProvider<System.IServiceProvider>.GetService()
    {
        return this;
    }
    
    object? global::System.IServiceProvider.GetService(global::System.Type type){
        if (type == typeof(InjectDemo.DatabaseCon)) return this.GetService<InjectDemo.DatabaseCon>();
        if (type == typeof(InjectDemo.IDatabase)) return this.GetService<InjectDemo.IDatabase>();
        if (type == typeof(System.IServiceProvider)) return this.GetService<System.IServiceProvider>();
        return null;
    }
    
    private global::System.Collections.Generic.List<object>? _disposables;
    
    private void TryAddDisposable(object? value){
        if (value is global::System.IDisposable || value is System.IAsyncDisposable)
        lock (this){
            (_disposables ??= new global::System.Collections.Generic.List<object>()).Add(value);
        }
    }
    
    public void Dispose(){
        void TryDispose(object? value) => (value as IDisposable)?.Dispose();
        
        TryDispose(_rootScope);
        if (_disposables != null){
            foreach (var service in _disposables){
                TryDispose(service);
            }
        }
    }
    
    public async global::System.Threading.Tasks.ValueTask DisposeAsync(){
        global::System.Threading.Tasks.ValueTask TryDispose(object? value){
            if (value is System.IAsyncDisposable asyncDisposable){
                return asyncDisposable.DisposeAsync();
            }
            else if (value is global::System.IDisposable disposable){
                disposable.Dispose();
            }
            return default;
        }
        
        await TryDispose(_rootScope);
        if (_disposables != null){
            foreach (var service in _disposables){
                await TryDispose(service);
            }
        }
    }
    
    [DebuggerHidden]
    public T GetService<T>() => this is IServiceProvider<T> provider ? provider.GetService() : throw CreateServiceNotFoundException<T>();
    
    [DebuggerHidden]
    public T GetService<T>(string name) => this is INamedServiceProvider<T> provider ? provider.GetService(name) : throw CreateServiceNotFoundException<T>(name);
    
    public Scope CreateScope() => new Scope(this);
    
    public partial class Scope : global::System.IDisposable,
       System.IAsyncDisposable,
       global::System.IServiceProvider,
       IServiceProvider<InjectDemo.DatabaseCon>,
       IServiceProvider<InjectDemo.IDatabase>,
       IServiceProvider<System.IServiceProvider>    
    {
        
        private MyServiceProvider _root;
        
        public Scope(MyServiceProvider root){
            _root = root;
        }
        
        [DebuggerHidden]
        public T GetService<T>() => this is IServiceProvider<T> provider ? provider.GetService() : throw CreateServiceNotFoundException<T>();
        
        [DebuggerHidden]
        public T GetService<T>(string name) => this is INamedServiceProvider<T> provider ? provider.GetService(name) : throw CreateServiceNotFoundException<T>(name);
        
        InjectDemo.DatabaseCon IServiceProvider<InjectDemo.DatabaseCon>.GetService(){
            InjectDemo.DatabaseCon service = new InjectDemo.DatabaseCon();
            TryAddDisposable(service);
            return service;
        }
        
        InjectDemo.IDatabase IServiceProvider<InjectDemo.IDatabase>.GetService(){
            InjectDemo.DatabaseCon service = new InjectDemo.DatabaseCon();
            TryAddDisposable(service);
            return service;
        }
        
        System.IServiceProvider IServiceProvider<System.IServiceProvider>.GetService(){
            return this;
        }
        
        object? global::System.IServiceProvider.GetService(global::System.Type type){
            if (type == typeof(InjectDemo.DatabaseCon)) return this.GetService<InjectDemo.DatabaseCon>();
            if (type == typeof(InjectDemo.IDatabase)) return this.GetService<InjectDemo.IDatabase>();
            if (type == typeof(System.IServiceProvider)) return this.GetService<System.IServiceProvider>();
            return null;
        }
        
        private global::System.Collections.Generic.List<object>? _disposables;
        
        private void TryAddDisposable(object? value){
            if (value is global::System.IDisposable || value is System.IAsyncDisposable)
            lock (this){
                (_disposables ??= new global::System.Collections.Generic.List<object>()).Add(value);
            }
        }
        
        public void Dispose(){
            void TryDispose(object? value) => (value as IDisposable)?.Dispose();
            
            if (_disposables != null){
                foreach (var service in _disposables){
                    TryDispose(service);
                }
            }
        }
        
        public async global::System.Threading.Tasks.ValueTask DisposeAsync(){
            global::System.Threading.Tasks.ValueTask TryDispose(object? value){
                if (value is System.IAsyncDisposable asyncDisposable){
                    return asyncDisposable.DisposeAsync();
                }
                else if (value is global::System.IDisposable disposable){
                    disposable.Dispose();
                }
                return default;
            }
            
            if (_disposables != null){
                foreach (var service in _disposables){
                    await TryDispose(service);
                }
            }
        }
        
    }
    private Scope GetRootScope(){
        if (_rootScope == default)
        lock (this)
        if (_rootScope == default){
            _rootScope = CreateScope();
        }
        return _rootScope;
    }
}

Code and pdf at

https://ignatandrei.github.io/RSCG_Examples/v2/docs/jab

RSCG – FunicularSwitch

name	FunicularSwitch
nuget	https://www.nuget.org/packages/FunicularSwitch.Generators/ https://www.nuget.org/packages/FunicularSwitch
link	https://github.com/bluehands/Funicular-Switch
author	bluehands

Generating discriminated unions for C# 9.0 and above.

This is how you can use FunicularSwitch .

The code that you start with is


<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net8.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
  </PropertyGroup>

 
	<PropertyGroup>
		<EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
		<CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath>
	</PropertyGroup>

 
	<ItemGroup>
	  <PackageReference Include="FunicularSwitch" Version="5.0.1" />
	  <PackageReference Include="FunicularSwitch.Generators" Version="3.2.0">
	    <PrivateAssets>all</PrivateAssets>
	    <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
	  </PackageReference>
	</ItemGroup>
</Project>

The code that you will use is


using Union;

Console.WriteLine("Save or not");
var data = SaveToDatabase.Save(0);

Console.WriteLine(data.Match(
    ok => true,
    error => false));
data = SaveToDatabase.Save(1);
Console.WriteLine(data.Match(ok => true, error => false));


namespace Union;

[FunicularSwitch.Generators.ResultType(ErrorType = typeof(ErrorDetails))]
public abstract partial class ResultSave<T> { };

public class ErrorDetails
{
    
}



    //[FunicularSwitch.Generators.UnionType]
    //public abstract partial class ResultSave { };

    //public sealed partial record Success(int Value): ResultSave;
    //public sealed partial record ValidationError(string Message):ResultSave;

    ////public sealed partial record Ok(T Value) : ResultSave<T>;

    ////public sealed partial record Error(Exception Exception) : ResultSave<T>;


using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Union;
internal class SaveToDatabase
{
    public static ResultSave<int> Save(int i)
    {
        if (i == 0)
        {
            return new ResultSave<int>.Error_(new ErrorDetails());
        }
        return new ResultSave<int>.Ok_(i);
    }
}

The code that is generated is

using System;

// ReSharper disable once CheckNamespace
namespace FunicularSwitch.Generators
{
    [AttributeUsage(AttributeTargets.Enum)]
    sealed class ExtendedEnumAttribute : Attribute
    {
	    public EnumCaseOrder CaseOrder { get; set; } = EnumCaseOrder.AsDeclared;
	    public ExtensionAccessibility Accessibility { get; set; } = ExtensionAccessibility.Public;
    }
    
    enum EnumCaseOrder
    {
        Alphabetic,
        AsDeclared
    }

    /// <summary>
    /// Generate match methods for all enums defined in assembly that contains AssemblySpecifier.
    /// </summary>
    [AttributeUsage(AttributeTargets.Assembly, AllowMultiple = true)]
    class ExtendEnumsAttribute : Attribute
    {
	    public Type AssemblySpecifier { get; }
	    public EnumCaseOrder CaseOrder { get; set; } = EnumCaseOrder.AsDeclared;
	    public ExtensionAccessibility Accessibility { get; set; } = ExtensionAccessibility.Public;

	    public ExtendEnumsAttribute() => AssemblySpecifier = typeof(ExtendEnumsAttribute);

	    public ExtendEnumsAttribute(Type assemblySpecifier)
	    {
		    AssemblySpecifier = assemblySpecifier;
	    }
    }

    /// <summary>
    /// Generate match methods for Type. Must be enum.
    /// </summary>
    [AttributeUsage(AttributeTargets.Assembly, AllowMultiple = true)]
    class ExtendEnumAttribute : Attribute
    {
	    public Type Type { get; }

	    public EnumCaseOrder CaseOrder { get; set; } = EnumCaseOrder.AsDeclared;

	    public ExtensionAccessibility Accessibility { get; set; } = ExtensionAccessibility.Public;

	    public ExtendEnumAttribute(Type type)
	    {
		    Type = type;
	    }
    }

    enum ExtensionAccessibility
    {
	    Internal,
	    Public
    }
}

using System;

// ReSharper disable once CheckNamespace
namespace FunicularSwitch.Generators
{
	/// <summary>
	/// Mark an abstract partial type with a single generic argument with the ResultType attribute.
	/// This type from now on has Ok | Error semantics with map and bind operations.
	/// </summary>
    [AttributeUsage(AttributeTargets.Class, Inherited = false)]
    sealed class ResultTypeAttribute : Attribute
    {
        public ResultTypeAttribute() => ErrorType = typeof(string);
        public ResultTypeAttribute(Type errorType) => ErrorType = errorType;

        public Type ErrorType { get; set; }
    }

    /// <summary>
    /// Mark a static method or a member method or you error type with the MergeErrorAttribute attribute.
    /// Static signature: TError -> TError -> TError. Member signature: TError -> TError
    /// We are now able to collect errors and methods like Validate, Aggregate, FirstOk that are useful to combine results are generated.
    /// </summary>
    [AttributeUsage(AttributeTargets.Method, Inherited = false)]
    sealed class MergeErrorAttribute : Attribute
    {
    }

    /// <summary>
    /// Mark a static method with the ExceptionToError attribute.
    /// Signature: Exception -> TError
    /// This method is always called, when an exception happens in a bind operation.
    /// So a call like result.Map(i => i/0) will return an Error produced by the factory method instead of throwing the DivisionByZero exception.
    /// </summary>
    [AttributeUsage(AttributeTargets.Method, Inherited = false)]
    sealed class ExceptionToError : Attribute
    {
    }
}

#nullable enable
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using FunicularSwitch;

namespace Union
{
#pragma warning disable 1591
    public abstract partial class ResultSave
    {
        public static ResultSave<T> Error<T>(ErrorDetails details) => new ResultSave<T>.Error_(details);
        public static ResultSave<T> Ok<T>(T value) => new ResultSave<T>.Ok_(value);
        public bool IsError => GetType().GetGenericTypeDefinition() == typeof(ResultSave<>.Error_);
        public bool IsOk => !IsError;
        public abstract ErrorDetails? GetErrorOrDefault();

        public static ResultSave<T> Try<T>(Func<T> action, Func<Exception, ErrorDetails> formatError)
        {
            try
            {
                return action();
            }
            catch (Exception e)
            {
                return Error<T>(formatError(e));
            }
        }

        public static async Task<ResultSave<T>> Try<T>(Func<Task<T>> action, Func<Exception, ErrorDetails> formatError)
        {
            try
            {
                return await action();
            }
            catch (Exception e)
            {
                return Error<T>(formatError(e));
            }
        }
    }

    public abstract partial class ResultSave<T> : ResultSave, IEnumerable<T>
    {
        public static ResultSave<T> Error(ErrorDetails message) => Error<T>(message);
        public static ResultSave<T> Ok(T value) => Ok<T>(value);

        public static implicit operator ResultSave<T>(T value) => ResultSave.Ok(value);

        public static bool operator true(ResultSave<T> result) => result.IsOk;
        public static bool operator false(ResultSave<T> result) => result.IsError;

        public static bool operator !(ResultSave<T> result) => result.IsError;

        //just here to suppress warning, never called because all subtypes (Ok_, Error_) implement Equals and GetHashCode
        bool Equals(ResultSave<T> other) => this switch
        {
            Ok_ ok => ok.Equals((object)other),
            Error_ error => error.Equals((object)other),
            _ => throw new InvalidOperationException($"Unexpected type derived from {nameof(ResultSave<T>)}")
        };

        public override int GetHashCode() => this switch
        {
            Ok_ ok => ok.GetHashCode(),
            Error_ error => error.GetHashCode(),
            _ => throw new InvalidOperationException($"Unexpected type derived from {nameof(ResultSave<T>)}")
        };

        public override bool Equals(object? obj)
        {
            if (ReferenceEquals(null, obj)) return false;
            if (ReferenceEquals(this, obj)) return true;
            if (obj.GetType() != this.GetType()) return false;
            return Equals((ResultSave<T>)obj);
        }

        public static bool operator ==(ResultSave<T>? left, ResultSave<T>? right) => Equals(left, right);

        public static bool operator !=(ResultSave<T>? left, ResultSave<T>? right) => !Equals(left, right);

        public void Match(Action<T> ok, Action<ErrorDetails>? error = null) => Match(
            v =>
            {
                ok.Invoke(v);
                return 42;
            },
            err =>
            {
                error?.Invoke(err);
                return 42;
            });

        public T1 Match<T1>(Func<T, T1> ok, Func<ErrorDetails, T1> error)
        {
            return this switch
            {
                Ok_ okResultSave => ok(okResultSave.Value),
                Error_ errorResultSave => error(errorResultSave.Details),
                _ => throw new InvalidOperationException($"Unexpected derived result type: {GetType()}")
            };
        }

        public async Task<T1> Match<T1>(Func<T, Task<T1>> ok, Func<ErrorDetails, Task<T1>> error)
        {
            return this switch
            {
                Ok_ okResultSave => await ok(okResultSave.Value).ConfigureAwait(false),
                Error_ errorResultSave => await error(errorResultSave.Details).ConfigureAwait(false),
                _ => throw new InvalidOperationException($"Unexpected derived result type: {GetType()}")
            };
        }

        public Task<T1> Match<T1>(Func<T, Task<T1>> ok, Func<ErrorDetails, T1> error) =>
            Match(ok, e => Task.FromResult(error(e)));

        public async Task Match(Func<T, Task> ok)
        {
            if (this is Ok_ okResultSave) await ok(okResultSave.Value).ConfigureAwait(false);
        }

        public T Match(Func<ErrorDetails, T> error) => Match(v => v, error);

        public ResultSave<T1> Bind<T1>(Func<T, ResultSave<T1>> bind)
        {
            switch (this)
            {
                case Ok_ ok:
	                try
	                {
		                return bind(ok.Value);
	                }
	                // ReSharper disable once RedundantCatchClause
#pragma warning disable CS0168 // Variable is declared but never used
	                catch (Exception e)
#pragma warning restore CS0168 // Variable is declared but never used
	                {
		                throw; //createGenericErrorResult
	                }
                case Error_ error:
                    return error.Convert<T1>();
                default:
                    throw new InvalidOperationException($"Unexpected derived result type: {GetType()}");
            }
        }

        public async Task<ResultSave<T1>> Bind<T1>(Func<T, Task<ResultSave<T1>>> bind)
        {
            switch (this)
            {
                case Ok_ ok:
	                try
	                {
		                return await bind(ok.Value).ConfigureAwait(false);
	                }
	                // ReSharper disable once RedundantCatchClause
#pragma warning disable CS0168 // Variable is declared but never used
	                catch (Exception e)
#pragma warning restore CS0168 // Variable is declared but never used
	                {
		                throw; //createGenericErrorResult
	                }
                case Error_ error:
                    return error.Convert<T1>();
                default:
                    throw new InvalidOperationException($"Unexpected derived result type: {GetType()}");
            }
        }

        public ResultSave<T1> Map<T1>(Func<T, T1> map)
            => Bind(value => Ok(map(value)));

        public Task<ResultSave<T1>> Map<T1>(Func<T, Task<T1>> map)
            => Bind(async value => Ok(await map(value).ConfigureAwait(false)));

        public T? GetValueOrDefault()
	        => Match(
		        v => (T?)v,
		        _ => default
	        );

        public T GetValueOrDefault(Func<T> defaultValue)
	        => Match(
		        v => v,
		        _ => defaultValue()
	        );

        public T GetValueOrDefault(T defaultValue)
	        => Match(
		        v => v,
		        _ => defaultValue
	        );

        public T GetValueOrThrow()
            => Match(
                v => v,
                details => throw new InvalidOperationException($"Cannot access error result value. Error: {details}"));

        public IEnumerator<T> GetEnumerator() => Match(ok => new[] { ok }, _ => Enumerable.Empty<T>()).GetEnumerator();

        public override string ToString() => Match(ok => $"Ok {ok?.ToString()}", error => $"Error {error}");
        IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();

        public sealed partial class Ok_ : ResultSave<T>
        {
            public T Value { get; }

            public Ok_(T value) => Value = value;

            public override ErrorDetails? GetErrorOrDefault() => null;

            public bool Equals(Ok_? other)
            {
                if (ReferenceEquals(null, other)) return false;
                if (ReferenceEquals(this, other)) return true;
                return EqualityComparer<T>.Default.Equals(Value, other.Value);
            }

            public override bool Equals(object? obj)
            {
                if (ReferenceEquals(null, obj)) return false;
                if (ReferenceEquals(this, obj)) return true;
                return obj is Ok_ other && Equals(other);
            }

            public override int GetHashCode() => Value == null ? 0 : EqualityComparer<T>.Default.GetHashCode(Value);

            public static bool operator ==(Ok_ left, Ok_ right) => Equals(left, right);

            public static bool operator !=(Ok_ left, Ok_ right) => !Equals(left, right);
        }

        public sealed partial class Error_ : ResultSave<T>
        {
            public ErrorDetails Details { get; }

            public Error_(ErrorDetails details) => Details = details;

            public ResultSave<T1>.Error_ Convert<T1>() => new ResultSave<T1>.Error_(Details);

            public override ErrorDetails? GetErrorOrDefault() => Details;

            public bool Equals(Error_? other)
            {
                if (ReferenceEquals(null, other)) return false;
                if (ReferenceEquals(this, other)) return true;
                return Equals(Details, other.Details);
            }

            public override bool Equals(object? obj)
            {
                if (ReferenceEquals(null, obj)) return false;
                if (ReferenceEquals(this, obj)) return true;
                return obj is Error_ other && Equals(other);
            }

            public override int GetHashCode() => Details.GetHashCode();

            public static bool operator ==(Error_ left, Error_ right) => Equals(left, right);

            public static bool operator !=(Error_ left, Error_ right) => !Equals(left, right);
        }

    }

    public static partial class ResultSaveExtension
    {
        #region bind

        public static async Task<ResultSave<T1>> Bind<T, T1>(
            this Task<ResultSave<T>> result,
            Func<T, ResultSave<T1>> bind)
            => (await result.ConfigureAwait(false)).Bind(bind);

        public static async Task<ResultSave<T1>> Bind<T, T1>(
            this Task<ResultSave<T>> result,
            Func<T, Task<ResultSave<T1>>> bind)
            => await (await result.ConfigureAwait(false)).Bind(bind).ConfigureAwait(false);

        #endregion

        #region map

        public static async Task<ResultSave<T1>> Map<T, T1>(
            this Task<ResultSave<T>> result,
            Func<T, T1> map)
            => (await result.ConfigureAwait(false)).Map(map);

        public static Task<ResultSave<T1>> Map<T, T1>(
            this Task<ResultSave<T>> result,
            Func<T, Task<T1>> bind)
            => Bind(result, async v => ResultSave.Ok(await bind(v).ConfigureAwait(false)));

        public static ResultSave<T> MapError<T>(this ResultSave<T> result, Func<ErrorDetails, ErrorDetails> mapError) =>
            result.Match(ok => ok, error => ResultSave.Error<T>(mapError(error)));

        #endregion

        #region match

        public static async Task<T1> Match<T, T1>(
            this Task<ResultSave<T>> result,
            Func<T, Task<T1>> ok,
            Func<ErrorDetails, Task<T1>> error)
            => await (await result.ConfigureAwait(false)).Match(ok, error).ConfigureAwait(false);

        public static async Task<T1> Match<T, T1>(
            this Task<ResultSave<T>> result,
            Func<T, Task<T1>> ok,
            Func<ErrorDetails, T1> error)
            => await (await result.ConfigureAwait(false)).Match(ok, error).ConfigureAwait(false);

        public static async Task<T1> Match<T, T1>(
            this Task<ResultSave<T>> result,
            Func<T, T1> ok,
            Func<ErrorDetails, T1> error)
            => (await result.ConfigureAwait(false)).Match(ok, error);

        #endregion

        public static ResultSave<T> Flatten<T>(this ResultSave<ResultSave<T>> result) => result.Bind(r => r);

        public static ResultSave<T1> As<T, T1>(this ResultSave<T> result, Func<ErrorDetails> errorTIsNotT1) =>
            result.Bind(r =>
            {
                if (r is T1 converted)
                    return converted;
                return ResultSave.Error<T1>(errorTIsNotT1());
            });

        public static ResultSave<T1> As<T1>(this ResultSave<object> result, Func<ErrorDetails> errorIsNotT1) =>
            result.As<object, T1>(errorIsNotT1);
        
        #region query-expression pattern
        
        public static ResultSave<T1> Select<T, T1>(this ResultSave<T> result, Func<T, T1> selector) => result.Map(selector);
        public static Task<ResultSave<T1>> Select<T, T1>(this Task<ResultSave<T>> result, Func<T, T1> selector) => result.Map(selector);
        
        public static ResultSave<T2> SelectMany<T, T1, T2>(this ResultSave<T> result, Func<T, ResultSave<T1>> selector, Func<T, T1, T2> resultSelector) => result.Bind(t => selector(t).Map(t1 => resultSelector(t, t1)));
        public static Task<ResultSave<T2>> SelectMany<T, T1, T2>(this Task<ResultSave<T>> result, Func<T, Task<ResultSave<T1>>> selector, Func<T, T1, T2> resultSelector) => result.Bind(t => selector(t).Map(t1 => resultSelector(t, t1)));
        public static Task<ResultSave<T2>> SelectMany<T, T1, T2>(this Task<ResultSave<T>> result, Func<T, ResultSave<T1>> selector, Func<T, T1, T2> resultSelector) => result.Bind(t => selector(t).Map(t1 => resultSelector(t, t1)));
        public static Task<ResultSave<T2>> SelectMany<T, T1, T2>(this ResultSave<T> result, Func<T, Task<ResultSave<T1>>> selector, Func<T, T1, T2> resultSelector) => result.Bind(t => selector(t).Map(t1 => resultSelector(t, t1)));

        #endregion
    }
}

namespace Union.Extensions
{
    public static partial class ResultSaveExtension
    {
        public static IEnumerable<T1> Choose<T, T1>(
            this IEnumerable<T> items,
            Func<T, ResultSave<T1>> choose,
            Action<ErrorDetails> onError)
            => items
                .Select(i => choose(i))
                .Choose(onError);

        public static IEnumerable<T> Choose<T>(
            this IEnumerable<ResultSave<T>> results,
            Action<ErrorDetails> onError)
            => results
                .Where(r =>
                    r.Match(_ => true, error =>
                    {
                        onError(error);
                        return false;
                    }))
                .Select(r => r.GetValueOrThrow());

        public static ResultSave<T> As<T>(this object item, Func<ErrorDetails> error) =>
            !(item is T t) ? ResultSave.Error<T>(error()) : t;

        public static ResultSave<T> NotNull<T>(this T? item, Func<ErrorDetails> error) =>
            item ?? ResultSave.Error<T>(error());

        public static ResultSave<string> NotNullOrEmpty(this string? s, Func<ErrorDetails> error)
            => string.IsNullOrEmpty(s) ? ResultSave.Error<string>(error()) : s!;

        public static ResultSave<string> NotNullOrWhiteSpace(this string? s, Func<ErrorDetails> error)
            => string.IsNullOrWhiteSpace(s) ? ResultSave.Error<string>(error()) : s!;

        public static ResultSave<T> First<T>(this IEnumerable<T> candidates, Func<T, bool> predicate, Func<ErrorDetails> noMatch) =>
            candidates
                .FirstOrDefault(i => predicate(i))
                .NotNull(noMatch);
    }
#pragma warning restore 1591
}

using System;

// ReSharper disable once CheckNamespace
namespace FunicularSwitch.Generators
{
    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Interface, Inherited = false)]
    sealed class UnionTypeAttribute : Attribute
    {
        public CaseOrder CaseOrder { get; set; } = CaseOrder.Alphabetic;
        public bool StaticFactoryMethods { get; set; } = true;
    }

    enum CaseOrder
    {
        Alphabetic,
        AsDeclared,
        Explicit
    }

    [AttributeUsage(AttributeTargets.Class, Inherited = false)]
    sealed class UnionCaseAttribute : Attribute
    {
        public UnionCaseAttribute(int index) => Index = index;

        public int Index { get; }
    }
}

Code and pdf at

https://ignatandrei.github.io/RSCG_Examples/v2/docs/FunicularSwitch

RSCG – CommandLine

name	CommandLine
nuget	https://www.nuget.org/packages/DotMake.CommandLine/
link	https://github.com/dotmake-build/command-line
author	DotMake

Generating easy command line applications.

This is how you can use CommandLine .

The code that you start with is


<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net8.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="DotMake.CommandLine" Version="1.8.0" />
  </ItemGroup>
	<PropertyGroup>
		<EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
		<CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath>
	</PropertyGroup>
</Project>

The code that you will use is


// See https://aka.ms/new-console-template for more information
using DotMake.CommandLine;

Cli.Run(([CliArgument] string PersonName, int  Age) =>
{
    Console.WriteLine($@"Value for {nameof(PersonName)} parameter is '{PersonName}'");
    Console.WriteLine($@"Value for {nameof(Age)} parameter is '{Age}'");
});


Cli.Run(([CliArgument] int idData) =>
{
    Console.WriteLine($@"Value for {nameof(idData)} parameter is '{idData}'");
    
});

The code that is generated is

// <auto-generated />
// Generated by DotMake.CommandLine.SourceGeneration v1.8.0.0
// Roslyn (Microsoft.CodeAnalysis) v4.800.23.57201
// Generation: 1

namespace GeneratedCode
{
    /// <inheritdoc />
    [DotMake.CommandLine.CliCommandAttribute]
    public class CliCommandAsDelegate_1ra93x8 : DotMake.CommandLine.CliCommandAsDelegateDefinition
    {
        /// <inheritdoc />
        [DotMake.CommandLine.CliArgumentAttribute]
        public int idData { get; set; }

        /// <inheritdoc />
        public void Run()
        {
            InvokeDelegate
            (
                "1ra93x8",
                new object[]
                {
                    idData, 
                }
            );
        }

        [System.Runtime.CompilerServices.ModuleInitializerAttribute]
        internal static void Initialize()
        {
            // Register this definition class so that it can be found by the command as delegate hash.
            Register<GeneratedCode.CliCommandAsDelegate_1ra93x8>("1ra93x8");
        }
    }
}

// <auto-generated />
// Generated by DotMake.CommandLine.SourceGeneration v1.8.0.0
// Roslyn (Microsoft.CodeAnalysis) v4.800.23.57201
// Generation: 1

namespace GeneratedCode
{
    /// <inheritdoc />
    public class CliCommandAsDelegate_1ra93x8Builder : DotMake.CommandLine.CliCommandBuilder
    {
        /// <inheritdoc />
        public CliCommandAsDelegate_1ra93x8Builder()
        {
            DefinitionType = typeof(GeneratedCode.CliCommandAsDelegate_1ra93x8);
            ParentDefinitionType = null;
            NameCasingConvention = DotMake.CommandLine.CliNameCasingConvention.KebabCase;
            NamePrefixConvention = DotMake.CommandLine.CliNamePrefixConvention.DoubleHyphen;
            ShortFormPrefixConvention = DotMake.CommandLine.CliNamePrefixConvention.SingleHyphen;
            ShortFormAutoGenerate = true;
        }

        private GeneratedCode.CliCommandAsDelegate_1ra93x8 CreateInstance()
        {
            return new GeneratedCode.CliCommandAsDelegate_1ra93x8();
        }

        /// <inheritdoc />
        public override System.CommandLine.CliCommand Build()
        {
            // Command for 'CliCommandAsDelegate_1ra93x8' class
            var rootCommand = new System.CommandLine.CliRootCommand()
            {
            };

            var defaultClass = CreateInstance();

            // Argument for 'idData' property
            var argument0 = new System.CommandLine.CliArgument<int>
            (
                "id-data"
            )
            {
            };
            argument0.CustomParser = GetParseArgument<int>
            (
                null
            );
            argument0.DefaultValueFactory = _ => defaultClass.idData;
            rootCommand.Add(argument0);

            // Add nested or external registered children
            foreach (var child in Children)
            {
                rootCommand.Add(child.Build());
            }

            BindFunc = (parseResult) =>
            {
                var targetClass = CreateInstance();

                //  Set the parsed or default values for the options

                //  Set the parsed or default values for the arguments
                targetClass.idData = GetValueForArgument(parseResult, argument0);

                return targetClass;
            };

            rootCommand.SetAction(parseResult =>
            {
                var targetClass = (GeneratedCode.CliCommandAsDelegate_1ra93x8) BindFunc(parseResult);

                //  Call the command handler
                var cliContext = new DotMake.CommandLine.CliContext(parseResult);
                var exitCode = 0;
                targetClass.Run();
                return exitCode;
            });

            return rootCommand;
        }

        [System.Runtime.CompilerServices.ModuleInitializerAttribute]
        internal static void Initialize()
        {
            var commandBuilder = new GeneratedCode.CliCommandAsDelegate_1ra93x8Builder();

            // Register this command builder so that it can be found by the definition class
            // and it can be found by the parent definition class if it's a nested/external child.
            commandBuilder.Register();
        }
    }
}

// <auto-generated />
// Generated by DotMake.CommandLine.SourceGeneration v1.8.0.0
// Roslyn (Microsoft.CodeAnalysis) v4.800.23.57201
// Generation: 2

namespace GeneratedCode
{
    /// <inheritdoc />
    [DotMake.CommandLine.CliCommandAttribute]
    public class CliCommandAsDelegate_34pdvjr : DotMake.CommandLine.CliCommandAsDelegateDefinition
    {
        /// <inheritdoc />
        [DotMake.CommandLine.CliArgumentAttribute]
        public string PersonName { get; set; }

        /// <inheritdoc />
        [DotMake.CommandLine.CliOptionAttribute]
        public int Age { get; set; }

        /// <inheritdoc />
        public void Run()
        {
            InvokeDelegate
            (
                "34pdvjr",
                new object[]
                {
                    PersonName, 
                    Age, 
                }
            );
        }

        [System.Runtime.CompilerServices.ModuleInitializerAttribute]
        internal static void Initialize()
        {
            // Register this definition class so that it can be found by the command as delegate hash.
            Register<GeneratedCode.CliCommandAsDelegate_34pdvjr>("34pdvjr");
        }
    }
}

// <auto-generated />
// Generated by DotMake.CommandLine.SourceGeneration v1.8.0.0
// Roslyn (Microsoft.CodeAnalysis) v4.800.23.57201
// Generation: 2

namespace GeneratedCode
{
    /// <inheritdoc />
    public class CliCommandAsDelegate_34pdvjrBuilder : DotMake.CommandLine.CliCommandBuilder
    {
        /// <inheritdoc />
        public CliCommandAsDelegate_34pdvjrBuilder()
        {
            DefinitionType = typeof(GeneratedCode.CliCommandAsDelegate_34pdvjr);
            ParentDefinitionType = null;
            NameCasingConvention = DotMake.CommandLine.CliNameCasingConvention.KebabCase;
            NamePrefixConvention = DotMake.CommandLine.CliNamePrefixConvention.DoubleHyphen;
            ShortFormPrefixConvention = DotMake.CommandLine.CliNamePrefixConvention.SingleHyphen;
            ShortFormAutoGenerate = true;
        }

        private GeneratedCode.CliCommandAsDelegate_34pdvjr CreateInstance()
        {
            return new GeneratedCode.CliCommandAsDelegate_34pdvjr();
        }

        /// <inheritdoc />
        public override System.CommandLine.CliCommand Build()
        {
            // Command for 'CliCommandAsDelegate_34pdvjr' class
            var rootCommand = new System.CommandLine.CliRootCommand()
            {
            };

            var defaultClass = CreateInstance();

            // Option for 'Age' property
            var option0 = new System.CommandLine.CliOption<int>
            (
                "--age"
            )
            {
                Required = false,
            };
            option0.CustomParser = GetParseArgument<int>
            (
                null
            );
            option0.DefaultValueFactory = _ => defaultClass.Age;
            option0.Aliases.Add("-a");
            rootCommand.Add(option0);

            // Argument for 'PersonName' property
            var argument0 = new System.CommandLine.CliArgument<string>
            (
                "person-name"
            )
            {
            };
            argument0.CustomParser = GetParseArgument<string>
            (
                null
            );
            rootCommand.Add(argument0);

            // Add nested or external registered children
            foreach (var child in Children)
            {
                rootCommand.Add(child.Build());
            }

            BindFunc = (parseResult) =>
            {
                var targetClass = CreateInstance();

                //  Set the parsed or default values for the options
                targetClass.Age = GetValueForOption(parseResult, option0);

                //  Set the parsed or default values for the arguments
                targetClass.PersonName = GetValueForArgument(parseResult, argument0);

                return targetClass;
            };

            rootCommand.SetAction(parseResult =>
            {
                var targetClass = (GeneratedCode.CliCommandAsDelegate_34pdvjr) BindFunc(parseResult);

                //  Call the command handler
                var cliContext = new DotMake.CommandLine.CliContext(parseResult);
                var exitCode = 0;
                targetClass.Run();
                return exitCode;
            });

            return rootCommand;
        }

        [System.Runtime.CompilerServices.ModuleInitializerAttribute]
        internal static void Initialize()
        {
            var commandBuilder = new GeneratedCode.CliCommandAsDelegate_34pdvjrBuilder();

            // Register this command builder so that it can be found by the definition class
            // and it can be found by the parent definition class if it's a nested/external child.
            commandBuilder.Register();
        }
    }
}

// <auto-generated />
// Generated by DotMake.CommandLine.SourceGeneration v1.8.0.0
// Roslyn (Microsoft.CodeAnalysis) v4.800.23.57201
// Generation: 2

namespace GeneratedCode
{
    /// <inheritdoc />
    [DotMake.CommandLine.CliCommandAttribute]
    public class CliCommandAsDelegate_3r0zsnc : DotMake.CommandLine.CliCommandAsDelegateDefinition
    {
        /// <inheritdoc />
        [DotMake.CommandLine.CliArgumentAttribute]
        public string arg1 { get; set; }

        /// <inheritdoc />
        [DotMake.CommandLine.CliOptionAttribute]
        public bool opt1 { get; set; }

        /// <inheritdoc />
        public void Run()
        {
            InvokeDelegate
            (
                "3r0zsnc",
                new object[]
                {
                    arg1, 
                    opt1, 
                }
            );
        }

        [System.Runtime.CompilerServices.ModuleInitializerAttribute]
        internal static void Initialize()
        {
            // Register this definition class so that it can be found by the command as delegate hash.
            Register<GeneratedCode.CliCommandAsDelegate_3r0zsnc>("3r0zsnc");
        }
    }
}

// <auto-generated />
// Generated by DotMake.CommandLine.SourceGeneration v1.8.0.0
// Roslyn (Microsoft.CodeAnalysis) v4.800.23.57201
// Generation: 2

namespace GeneratedCode
{
    /// <inheritdoc />
    public class CliCommandAsDelegate_3r0zsncBuilder : DotMake.CommandLine.CliCommandBuilder
    {
        /// <inheritdoc />
        public CliCommandAsDelegate_3r0zsncBuilder()
        {
            DefinitionType = typeof(GeneratedCode.CliCommandAsDelegate_3r0zsnc);
            ParentDefinitionType = null;
            NameCasingConvention = DotMake.CommandLine.CliNameCasingConvention.KebabCase;
            NamePrefixConvention = DotMake.CommandLine.CliNamePrefixConvention.DoubleHyphen;
            ShortFormPrefixConvention = DotMake.CommandLine.CliNamePrefixConvention.SingleHyphen;
            ShortFormAutoGenerate = true;
        }

        private GeneratedCode.CliCommandAsDelegate_3r0zsnc CreateInstance()
        {
            return new GeneratedCode.CliCommandAsDelegate_3r0zsnc();
        }

        /// <inheritdoc />
        public override System.CommandLine.CliCommand Build()
        {
            // Command for 'CliCommandAsDelegate_3r0zsnc' class
            var rootCommand = new System.CommandLine.CliRootCommand()
            {
            };

            var defaultClass = CreateInstance();

            // Option for 'opt1' property
            var option0 = new System.CommandLine.CliOption<bool>
            (
                "--opt-1"
            )
            {
                Required = false,
            };
            option0.CustomParser = GetParseArgument<bool>
            (
                null
            );
            option0.DefaultValueFactory = _ => defaultClass.opt1;
            option0.Aliases.Add("-o");
            rootCommand.Add(option0);

            // Argument for 'arg1' property
            var argument0 = new System.CommandLine.CliArgument<string>
            (
                "arg-1"
            )
            {
            };
            argument0.CustomParser = GetParseArgument<string>
            (
                null
            );
            rootCommand.Add(argument0);

            // Add nested or external registered children
            foreach (var child in Children)
            {
                rootCommand.Add(child.Build());
            }

            BindFunc = (parseResult) =>
            {
                var targetClass = CreateInstance();

                //  Set the parsed or default values for the options
                targetClass.opt1 = GetValueForOption(parseResult, option0);

                //  Set the parsed or default values for the arguments
                targetClass.arg1 = GetValueForArgument(parseResult, argument0);

                return targetClass;
            };

            rootCommand.SetAction(parseResult =>
            {
                var targetClass = (GeneratedCode.CliCommandAsDelegate_3r0zsnc) BindFunc(parseResult);

                //  Call the command handler
                var cliContext = new DotMake.CommandLine.CliContext(parseResult);
                var exitCode = 0;
                targetClass.Run();
                return exitCode;
            });

            return rootCommand;
        }

        [System.Runtime.CompilerServices.ModuleInitializerAttribute]
        internal static void Initialize()
        {
            var commandBuilder = new GeneratedCode.CliCommandAsDelegate_3r0zsncBuilder();

            // Register this command builder so that it can be found by the definition class
            // and it can be found by the parent definition class if it's a nested/external child.
            commandBuilder.Register();
        }
    }
}

Code and pdf at

https://ignatandrei.github.io/RSCG_Examples/v2/docs/CommandLine

More than100 examples of RSCG

I am deeply into Roslyn Source Code Generators. I like when code generates code . So I have created ones and make inventory of others . You can find the examples here by date : https://ignatandrei.github.io/RSCG_Examples/v2/docs/List-of-RSCG and by category https://ignatandrei.github.io/RSCG_Examples/v2/docs/rscg-examples

I have started when they appeared, with ISourceGenerator and now I am fond , even if the interface

IIncrementalGenerator https://learn.microsoft.com/en-us/dotnet/api/microsoft.codeanalysis.iincrementalgenerator?view=roslyn-dotnet-4.7.0 adds some learning curve.

Some thoughts:

Being code ( even generated) has , obvious, bugs. Can be improved
Microsoft is pushing those – for the moments, are 12 : List of RSCG | RSCG Examples (ignatandrei.github.io) . However, for AOT , seems to be the direction
Some are just glorified interpretors – for example, 103 – HangfireRecurringJob | RSCG Examples (ignatandrei.github.io) – translates an attribute to code. But also does a Mapper
There are many ways to do same thing – see mapper category again at 105 RSCG by category | RSCG Examples (ignatandrei.github.io)
To see the generated files put into the .csproj

<PropertyGroup>
<EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
<CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath>
</PropertyGroup>

Aspire & Intro to GitHub Copilot

Azi , la 19:30

Prezentare 1: Aspire – running multiple services
Descriere: Utilizare Aspire pentru vizualizare multiple servicii, open telemetry, frontend , backend, containere
Prezentator: Andrei Ignat, http://msprogrammer.serviciipeweb.ro/

Prezentare 2: Intro to GitHub Copilot
Descriere : Voi prezenta:
– la ce am folosit eu Copilot
– ⁠ce e nou în Copilot Chat
– ⁠vom încerca să facem un joc de la zero – doar cu cod generat pe baza unei prezentări de la MS Build 2023 –
Prezentator : Julian (Iulian) Atanasoae , https://www.linkedin.com/in/julianatanasoae/

Va astept la https://meet.google.com/pmm-oeyc-dmy

RSCG – NetAutomaticInterface

name	NetAutomaticInterface
nuget	https://www.nuget.org/packages/AutomaticInterface/
link	https://github.com/codecentric/net_automatic_interface
author	codecentric AG

GEnerating interface from class

This is how you can use NetAutomaticInterface .

The code that you start with is


<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net8.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
  </PropertyGroup>

	<PropertyGroup>
		<EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
		<CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath>
	</PropertyGroup>

	<ItemGroup>
	  <PackageReference Include="AutomaticInterface" Version="2.1.0" OutputItemType="Analyzer" >
	    <PrivateAssets>all</PrivateAssets>
	    <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
	  </PackageReference>
	</ItemGroup>
</Project>

The code that you will use is


// See https://aka.ms/new-console-template for more information
using Class2Interface;

Console.WriteLine("Hello, World!");
IPerson person=new Person();
person.FirstName="Andrei";
person.LastName="Ignat";
Console.WriteLine(person.FullName());


[AttributeUsage(AttributeTargets.Class)]
public class GenerateAutomaticInterfaceAttribute : Attribute
{
    public GenerateAutomaticInterfaceAttribute(string namespaceName = "") { }
}


namespace Class2Interface;
[GenerateAutomaticInterface("Class2Interface")]
internal class Person:IPerson
{
    public int ID { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public string Name
    {
        get
        {
            return $"{FirstName} {LastName}";
        }
    }
    public string FullName()=>$"{FirstName} {LastName}";
}

The code that is generated is

//--------------------------------------------------------------------------------------------------
// <auto-generated>
//     This code was generated by a tool.
//
//     Changes to this file may cause incorrect behavior and will be lost if the code is regenerated.
// </auto-generated>
//--------------------------------------------------------------------------------------------------

using System.CodeDom.Compiler;

namespace Class2Interface
{
    [GeneratedCode("AutomaticInterface", "")]
    public partial interface IPerson
    {
        /// <inheritdoc />
        int ID { get; set; }
        
        /// <inheritdoc />
        string FirstName { get; set; }
        
        /// <inheritdoc />
        string LastName { get; set; }
        
        /// <inheritdoc />
        string Name { get; }
        
        /// <inheritdoc />
        string FullName();
        
    }
}

Code and pdf at

https://ignatandrei.github.io/RSCG_Examples/v2/docs/NetAutomaticInterface

Friday links 556

RSCG – WhatIAmDoing

name	WhatIAmDoing
nuget	https://www.nuget.org/packages/RSCG_WhatIAmDoing/ https://www.nuget.org/packages/RSCG_WhatIAmDoing_Common/
link	https://github.com/ignatandrei/RSCG_WhatIAmDoing
author	Ignat Andrei

Intercept any method in any project

This is how you can use WhatIAmDoing .

The code that you start with is


<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net8.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
  </PropertyGroup>

	<ItemGroup>
		<!-- <PackageReference Include="Microsoft.Extensions.Caching.Memory" Version="8.0.0" /> -->
		<PackageReference Include="RSCG_WhatIAmDoing" Version="8.2024.10201.735" />
		<PackageReference Include="RSCG_WhatIAmDoing_Common" Version="8.2024.10201.735" />
	</ItemGroup>

	<PropertyGroup>

		<EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
		<CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath>
		<InterceptorsPreviewNamespaces>$(InterceptorsPreviewNamespaces);RSCG_InterceptorTemplate</InterceptorsPreviewNamespaces>
	</PropertyGroup>

</Project>

The code that you will use is


using RSCG_WhatIAmDoing_Common;

Console.WriteLine("Hello, World!");
var data = CachingData.Methods().ToArray();

foreach (var item in data)
{
    Console.WriteLine($"Method {item.typeAndMethodData.MethodName} from class {item.typeAndMethodData.TypeOfClass} Time: {item.StartedAtDate} state {item.State} ");
    Console.WriteLine($"  =>Arguments: {item.ArgumentsAsString()}");
    if ((item.State & AccumulatedStateMethod.HasResult) == AccumulatedStateMethod.HasResult)
    {
        Console.WriteLine($"  =>Result: {item.Result}");
    }

}


using RSCG_WhatIAmDoing;
using RSCG_WhatIAmDoing_Common;

namespace WIADDemo;
//[ExposeClass(typeof(Encoding), nameof(Encoding.EncodingName))]
[InterceptStatic("System.Console.*")] // regex
internal class InterceptorMethodStatic : InterceptorMethodStaticBase, IInterceptorMethodStatic
{

}

The code that is generated is

#pragma warning disable CS1591 
#pragma warning disable CS9113
namespace System.Runtime.CompilerServices{
[AttributeUsage(AttributeTargets.Method,AllowMultiple =true)]
file class InterceptsLocationAttribute(string filePath, int line, int character) : Attribute
{
}
}//end namespace

namespace RSCG_InterceptorTemplate{
static partial class SimpleIntercept
{


//replace code:Console.WriteLine("Hello, World!");
//replace code:123456789!123456789!123456789!12345
[System.Runtime.CompilerServices.InterceptsLocation(@"D:\gth\RSCG_Examples\v2\rscg_examples\WIAD\src\WIADDemo\WIADDemo\Program.cs", 3, 9)]
    
//[System.Diagnostics.DebuggerStepThrough()]
public static  void Intercept__WriteLine_0 (  string? value )  
{

System.Collections.Generic.Dictionary<string,string?> valValues = new (){


};//end valValues

System.Collections.Generic.Dictionary<string,string?> stringValues = new() {


                { "value", value  ?.ToString() } ,
            };//end stringValues

        System.Collections.Generic.Dictionary<string,string?>
            expValues = new() {

            };//end exposeValues


        var x=WIADDemo.InterceptorMethodStatic .InterceptStaticMethodBefore(
$$$""""
    {"IsVoid":true,"Tag":"","MethodName":"WriteLine","TypeOfClass":"System.Console"}
""""
            ,valValues , stringValues , expValues
)
; 


                try{

                 System.Console.WriteLine(value);

                WIADDemo.InterceptorMethodStatic .InterceptMethodAfterWithoutResult(x);
                
                }

            
        
            catch(System.Exception ex){
                WIADDemo.InterceptorMethodStatic .InterceptMethodException(x,ex);
                throw;
            }
            finally{
                WIADDemo.InterceptorMethodStatic .InterceptMethodFinally(x);
            }
        
}
                

}//end class

}//namespace RSCG_InterceptorTemplate

#pragma warning disable CS1591 
#pragma warning disable CS9113
namespace System.Runtime.CompilerServices{
[AttributeUsage(AttributeTargets.Method,AllowMultiple =true)]
file class InterceptsLocationAttribute(string filePath, int line, int character) : Attribute
{
}
}//end namespace

namespace RSCG_InterceptorTemplate{
static partial class SimpleIntercept
{


//replace code:    Console.WriteLine($"Method {item.typeAndMethodData.MethodName} from class {item.typeAndMethodData.TypeOfClass} Time: {item.StartedAtDate} state {item.State} ");
//replace code:123456789!123456789!123456789!123456789!123456789!123456789!123456789!123456789!123456789!123456789!123456789!123456789!123456789!123456789!123456789!123456789!1234
[System.Runtime.CompilerServices.InterceptsLocation(@"D:\gth\RSCG_Examples\v2\rscg_examples\WIAD\src\WIADDemo\WIADDemo\Program.cs", 8, 13)]
    
//[System.Diagnostics.DebuggerStepThrough()]
public static  void Intercept__WriteLine_1 (  string? value )  
{

System.Collections.Generic.Dictionary<string,string?> valValues = new (){


};//end valValues

System.Collections.Generic.Dictionary<string,string?> stringValues = new() {


                { "value", value  ?.ToString() } ,
            };//end stringValues

        System.Collections.Generic.Dictionary<string,string?>
            expValues = new() {

            };//end exposeValues


        var x=WIADDemo.InterceptorMethodStatic .InterceptStaticMethodBefore(
$$$""""
    {"IsVoid":true,"Tag":"","MethodName":"WriteLine","TypeOfClass":"System.Console"}
""""
            ,valValues , stringValues , expValues
)
; 


                try{

                 System.Console.WriteLine(value);

                WIADDemo.InterceptorMethodStatic .InterceptMethodAfterWithoutResult(x);
                
                }

            
        
            catch(System.Exception ex){
                WIADDemo.InterceptorMethodStatic .InterceptMethodException(x,ex);
                throw;
            }
            finally{
                WIADDemo.InterceptorMethodStatic .InterceptMethodFinally(x);
            }
        
}
                

}//end class

}//namespace RSCG_InterceptorTemplate

#pragma warning disable CS1591 
#pragma warning disable CS9113
namespace System.Runtime.CompilerServices{
[AttributeUsage(AttributeTargets.Method,AllowMultiple =true)]
file class InterceptsLocationAttribute(string filePath, int line, int character) : Attribute
{
}
}//end namespace

namespace RSCG_InterceptorTemplate{
static partial class SimpleIntercept
{


//replace code:    Console.WriteLine($"  =>Arguments: {item.ArgumentsAsString()}");
//replace code:123456789!123456789!123456789!123456789!123456789!123456789!12345678
[System.Runtime.CompilerServices.InterceptsLocation(@"D:\gth\RSCG_Examples\v2\rscg_examples\WIAD\src\WIADDemo\WIADDemo\Program.cs", 9, 13)]
    
//[System.Diagnostics.DebuggerStepThrough()]
public static  void Intercept__WriteLine_2 (  string? value )  
{

System.Collections.Generic.Dictionary<string,string?> valValues = new (){


};//end valValues

System.Collections.Generic.Dictionary<string,string?> stringValues = new() {


                { "value", value  ?.ToString() } ,
            };//end stringValues

        System.Collections.Generic.Dictionary<string,string?>
            expValues = new() {

            };//end exposeValues


        var x=WIADDemo.InterceptorMethodStatic .InterceptStaticMethodBefore(
$$$""""
    {"IsVoid":true,"Tag":"","MethodName":"WriteLine","TypeOfClass":"System.Console"}
""""
            ,valValues , stringValues , expValues
)
; 


                try{

                 System.Console.WriteLine(value);

                WIADDemo.InterceptorMethodStatic .InterceptMethodAfterWithoutResult(x);
                
                }

            
        
            catch(System.Exception ex){
                WIADDemo.InterceptorMethodStatic .InterceptMethodException(x,ex);
                throw;
            }
            finally{
                WIADDemo.InterceptorMethodStatic .InterceptMethodFinally(x);
            }
        
}
                

}//end class

}//namespace RSCG_InterceptorTemplate

#pragma warning disable CS1591 
#pragma warning disable CS9113
namespace System.Runtime.CompilerServices{
[AttributeUsage(AttributeTargets.Method,AllowMultiple =true)]
file class InterceptsLocationAttribute(string filePath, int line, int character) : Attribute
{
}
}//end namespace

namespace RSCG_InterceptorTemplate{
static partial class SimpleIntercept
{


//replace code:        Console.WriteLine($"  =>Result: {item.Result}");
//replace code:123456789!123456789!123456789!123456789!123456789!123456
[System.Runtime.CompilerServices.InterceptsLocation(@"D:\gth\RSCG_Examples\v2\rscg_examples\WIAD\src\WIADDemo\WIADDemo\Program.cs", 12, 17)]
    
//[System.Diagnostics.DebuggerStepThrough()]
public static  void Intercept__WriteLine_3 (  string? value )  
{

System.Collections.Generic.Dictionary<string,string?> valValues = new (){


};//end valValues

System.Collections.Generic.Dictionary<string,string?> stringValues = new() {


                { "value", value  ?.ToString() } ,
            };//end stringValues

        System.Collections.Generic.Dictionary<string,string?>
            expValues = new() {

            };//end exposeValues


        var x=WIADDemo.InterceptorMethodStatic .InterceptStaticMethodBefore(
$$$""""
    {"IsVoid":true,"Tag":"","MethodName":"WriteLine","TypeOfClass":"System.Console"}
""""
            ,valValues , stringValues , expValues
)
; 


                try{

                 System.Console.WriteLine(value);

                WIADDemo.InterceptorMethodStatic .InterceptMethodAfterWithoutResult(x);
                
                }

            
        
            catch(System.Exception ex){
                WIADDemo.InterceptorMethodStatic .InterceptMethodException(x,ex);
                throw;
            }
            finally{
                WIADDemo.InterceptorMethodStatic .InterceptMethodFinally(x);
            }
        
}
                

}//end class

}//namespace RSCG_InterceptorTemplate

Code and pdf at

https://ignatandrei.github.io/RSCG_Examples/v2/docs/WhatIAmDoing

RSCG – NotNotAppSettings

name	NotNotAppSettings
nuget	https://www.nuget.org/packages/NotNot.AppSettings/
link	https://github.com/jasonswearingen/NotNot.AppSettings/
author	jasonswearingen

Application Settings to strongly typed classes. Generate also from AppSettings development

This is how you can use NotNotAppSettings .

The code that you start with is


<Project Sdk="Microsoft.NET.Sdk.Web">

  <PropertyGroup>
    <TargetFramework>net8.0</TargetFramework>
    <Nullable>enable</Nullable>
    <ImplicitUsings>enable</ImplicitUsings>
    <InvariantGlobalization>true</InvariantGlobalization>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Microsoft.AspNetCore.OpenApi" Version="8.0.1" />
    <PackageReference Include="NotNot.AppSettings" Version="1.0.0" OutputItemType="Analyzer" ReferenceOutputAssembly="true" />
    <PackageReference Include="Swashbuckle.AspNetCore" Version="6.4.0" />
  </ItemGroup>

  <ItemGroup>
    <AdditionalFiles Update="appsettings.json">
      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
    </AdditionalFiles>
  </ItemGroup>
	<PropertyGroup>
		<EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
		<CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath>
	</PropertyGroup>
</Project>

The code that you will use is


var builder = WebApplication.CreateBuilder(args);

// Add services to the container.
// Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();
builder.Services.AddSingleton<TestAppSettings.AppSettingsGen.IAppSettingsBinder, TestAppSettings.AppSettingsGen.AppSettingsBinder>();

var app = builder.Build();

// Configure the HTTP request pipeline.
if (app.Environment.IsDevelopment())
{
    app.UseSwagger();
    app.UseSwaggerUI();
}

app.UseHttpsRedirection();

var summaries = new[]
{
    "Freezing", "Bracing", "Chilly", "Cool", "Mild", "Warm", "Balmy", "Hot", "Sweltering", "Scorching"
};

var appSettings = app.Services.GetRequiredService<TestAppSettings.AppSettingsGen.IAppSettingsBinder>().AppSettings;
Console.WriteLine(appSettings.AppName);

app.MapGet("/weatherforecast", () =>
{
    var forecast = Enumerable.Range(1, 5).Select(index =>
        new WeatherForecast
        (
            DateOnly.FromDateTime(DateTime.Now.AddDays(index)),
            Random.Shared.Next(-20, 55),
            summaries[Random.Shared.Next(summaries.Length)]
        ))
        .ToArray();
    return forecast;
})
.WithName("GetWeatherForecast")
.WithOpenApi();

app.Run();

internal record WeatherForecast(DateOnly Date, int TemperatureC, string? Summary)
{
    public int TemperatureF => 32 + (int)(TemperatureC / 0.5556);
}

The code that is generated is


/** 
 * This file is generated by the NotNot.AppSettings nuget package.
 * Do not edit this file directly, instead edit the appsettings.json files and rebuild the project.
**/
using System;
using System.Runtime.CompilerServices;
namespace TestAppSettings.AppSettingsGen;

[CompilerGenerated]
public partial class AppSettings {
   public TestAppSettings.AppSettingsGen._AppSettings.Logging? Logging{get; set;}
   public string? AllowedHosts{get; set;}
   public string? AppName{get; set;}

}


/** 
 * This file is generated by the NotNot.AppSettings nuget package.
 * Do not edit this file directly, instead edit the appsettings.json files and rebuild the project.
**/
using System;
using System.Runtime.CompilerServices;
namespace TestAppSettings.AppSettingsGen._AppSettings;

[CompilerGenerated]
public partial class Logging {
   public TestAppSettings.AppSettingsGen._AppSettings._Logging.LogLevel? LogLevel{get; set;}

}


/** 
 * This file is generated by the NotNot.AppSettings nuget package.
 * Do not edit this file directly, instead edit the appsettings.json files and rebuild the project.
**/
using System;
using System.Runtime.CompilerServices;
namespace TestAppSettings.AppSettingsGen._AppSettings._Logging;

[CompilerGenerated]
public partial class LogLevel {
   public string? Default{get; set;}
   public string? Microsoft_AspNetCore{get; set;}

}


/** 
 * This file is generated by the NotNot.AppSettings nuget package.
 * Do not edit this file directly, instead edit the appsettings.json files and rebuild the project.
**/

using Microsoft.Extensions.Configuration;
namespace TestAppSettings.AppSettingsGen;


/// <summary>
/// Strongly typed AppSettings.json, recreated every build. 
/// <para>You can use this directly, extend it (it's a partial class), 
/// or get a populated instance of it via the <see cref="AppSettingsBinder"/> DI service</para>
/// </summary>
public partial class AppSettings
{
}

/// <summary>
/// a DI service that contains a strongly-typed copy of your appsettings.json
/// <para><strong>DI Usage:</strong></para>
/// <para><c>builder.Services.AddSingleton&lt;IAppSettingsBinder, AppSettingsBinder&gt;();</c></para>
/// <para><c>var app = builder.Build();</c></para>
///  <para><c>var appSettings = app.Services.GetRequiredService&lt;IAppSettingsBinder&gt;().AppSettings;</c></para>
/// <para><strong>Non-DI Usage:</strong></para>
/// <para><c>var appSettings = AppSettingsBinder.LoadDirect();</c></para>
/// </summary>
public partial class AppSettingsBinder : IAppSettingsBinder
{
   public AppSettings AppSettings { get; protected set; }

   public AppSettingsBinder(IConfiguration _config)
   {
      AppSettings = new AppSettings();

      //automatically reads and binds to config file
      _config.Bind(AppSettings);
   }

   /// <summary>
   /// Manually construct an AppSettings from your appsettings.json files.
   /// <para>NOTE: This method is provided for non-DI users.  If you use DI, don't use this method.  Instead just register this class as a service.</para>
   /// </summary>
   /// <param name="appSettingsLocation">folder where to search for appsettings.json.  defaults to current app folder.</param>
   /// <param name="appSettingsFileNames">lets you override the files to load up.  defaults to 'appsettings.json' and 'appsettings.{DOTNET_ENVIRONMENT}.json'</param>
   /// <param name="throwIfFilesMissing">default is to silently ignore if any of the .json files are missing.</param>
   /// <returns>your strongly typed appsettings with values from your .json loaded in</returns>
   public static AppSettings LoadDirect(string? appSettingsLocation = null,IEnumerable<string>? appSettingsFileNames=null,bool throwIfFilesMissing=false )
   {      
      //pick what .json files to load
      if (appSettingsFileNames is null)
      {
         //figure out what env
         var env = Environment.GetEnvironmentVariable("ASPNETCORE_ENVIRONMENT");
         env ??= Environment.GetEnvironmentVariable("DOTNET_ENVIRONMENT");
         env ??= Environment.GetEnvironmentVariable("ENVIRONMENT");
         //env ??= "Development"; //default to "Development
         if (env is null)
         {
            appSettingsFileNames = new[] { "appsettings.json" };
         }
         else
         {
            appSettingsFileNames = new[] { "appsettings.json", $"appsettings.{env}.json" };
         }
      }

      //build a config from the specified files
      var builder = new ConfigurationBuilder();
      if (appSettingsLocation != null)
      {
         builder.SetBasePath(appSettingsLocation);
      }
      var optional = !throwIfFilesMissing;
      foreach (var fileName in appSettingsFileNames)
      {         
         builder.AddJsonFile(fileName, optional: optional, reloadOnChange: false); // Add appsettings.json
      }
      IConfigurationRoot configuration = builder.Build();

      //now finally get the appsettings we care about
      var binder = new AppSettingsBinder(configuration);
      return binder.AppSettings;
   }
}

/// <summary>
/// a DI service that contains a strongly-typed copy of your appsettings.json
/// <para><strong>DI Usage:</strong></para>
/// <para><c>builder.Services.AddSingleton&lt;IAppSettingsBinder, AppSettingsBinder&gt;();</c></para>
/// <para><c>var app = builder.Build();</c></para>
///  <para><c>var appSettings = app.Services.GetRequiredService&lt;IAppSettingsBinder&gt;().AppSettings;</c></para>
/// <para><strong>Non-DI Usage:</strong></para>
/// <para><c>var appSettings = AppSettingsBinder.LoadDirect();</c></para>
/// </summary>
public interface IAppSettingsBinder
{
   public AppSettings AppSettings { get; }
}

Code and pdf at

https://ignatandrei.github.io/RSCG_Examples/v2/docs/NotNotAppSettings

Azi , la 19:30

Andrei Ignat weekly software news(mostly .NET)