RSCG – Sera.Union

RSCG – Sera.Union
 
 

Generate tagged union

This is how you can use Sera.Union .

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="Sera.Union" Version="0.7.0" />
	</ItemGroup>

</Project>

The code that you will use is

using UnionTypesDemo;

Console.WriteLine("Save or not");
var data = SaveToDatabase.Save(0);
Console.WriteLine(data.IsNotFound);
data = SaveToDatabase.Save(1);
if(data.IsOk)
{
    Console.WriteLine(data.Tag);
    Console.WriteLine(data.Ok);
}

The code that is generated is

// <auto-generated/>

#nullable enable

using Sera.TaggedUnion;

namespace UnionTypesDemo {

public partial struct ResultSave
    : global::Sera.TaggedUnion.ITaggedUnion
,global::System.IEquatable<ResultSave>
,global::System.IComparable<ResultSave>
#if NET7_0_OR_GREATER
,global::System.Numerics.IEqualityOperators<ResultSave,ResultSave,bool>
,global::System.Numerics.IComparisonOperators<ResultSave,ResultSave,bool>
#endif
{
    private __impl_ _impl;
    private ResultSave(__impl_ _impl) { this._impl = _impl; }

    public readonly Tags Tag
    {
        [global::System.Runtime.CompilerServices.MethodImpl(global::System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
        get => this._impl._tag;
    }

    public enum Tags : byte
    {
        Ok = 1,
        NotFound = 2,
    }

    [global::System.Runtime.CompilerServices.CompilerGenerated]
    private struct __impl_
    {
        public __unmanaged_ _unmanaged_;
        public readonly Tags _tag;

        [global::System.Runtime.CompilerServices.CompilerGenerated]
        [global::System.Runtime.InteropServices.StructLayout(global::System.Runtime.InteropServices.LayoutKind.Explicit)]
        internal struct __unmanaged_
        {
            [global::System.Runtime.InteropServices.FieldOffset(0)]
            public int _0;
        }

        public __impl_(Tags _tag)
        {
            global::System.Runtime.CompilerServices.Unsafe.SkipInit(out this._unmanaged_);
            this._tag = _tag;
        }
    }

    [global::System.Runtime.CompilerServices.MethodImpl(global::System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
    public static ResultSave MakeOk(int value)
    {
        var _impl = new __impl_(Tags.Ok);
        _impl._unmanaged_._0 = value;
        return new ResultSave(_impl);
    }
    [global::System.Runtime.CompilerServices.MethodImpl(global::System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
    public static ResultSave MakeNotFound()
    {
        var _impl = new __impl_(Tags.NotFound);
        return new ResultSave(_impl);
    }

    public readonly bool IsOk
    {
        [global::System.Runtime.CompilerServices.MethodImpl(global::System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
        get => this._impl._tag == Tags.Ok;
    }
    public readonly bool IsNotFound
    {
        [global::System.Runtime.CompilerServices.MethodImpl(global::System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
        get => this._impl._tag == Tags.NotFound;
    }

    public int Ok
    {
        [global::System.Runtime.CompilerServices.MethodImpl(global::System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
        readonly get => !this.IsOk ? default! : this._impl._unmanaged_._0!;
        [global::System.Runtime.CompilerServices.MethodImpl(global::System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
        set { if (this.IsOk) { this._impl._unmanaged_._0 = value; } }
    }

    [global::System.Runtime.CompilerServices.MethodImpl(global::System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
    public readonly bool Equals(ResultSave other) => this.Tag != other.Tag ? false : this.Tag switch
    {
        Tags.Ok => global::System.Collections.Generic.EqualityComparer<int>.Default.Equals(this.Ok,other.Ok),
        _ => true,
    };

    [global::System.Runtime.CompilerServices.MethodImpl(global::System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
    public readonly override int GetHashCode() => this.Tag switch
    {
        Tags.Ok => global::System.HashCode.Combine(this.Tag,this.Ok),
        _ => global::System.HashCode.Combine(this.Tag),
    };

    [global::System.Runtime.CompilerServices.MethodImpl(global::System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
    public readonly override bool Equals(object? obj) => obj is ResultSave other && Equals(other);

    [global::System.Runtime.CompilerServices.MethodImpl(global::System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
    public static bool operator ==(ResultSave left,ResultSave right) => Equals(left,right);
    [global::System.Runtime.CompilerServices.MethodImpl(global::System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
    public static bool operator !=(ResultSave left,ResultSave right) => !Equals(left,right);

    [global::System.Runtime.CompilerServices.MethodImpl(global::System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
    public readonly int CompareTo(ResultSave other) => this.Tag != other.Tag ? global::System.Collections.Generic.Comparer<Tags>.Default.Compare(this.Tag,other.Tag) : this.Tag switch
    {
        Tags.Ok => global::System.Collections.Generic.Comparer<int>.Default.Compare(this.Ok,other.Ok),
        _ => 0,
    };

    [global::System.Runtime.CompilerServices.MethodImpl(global::System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
    public static bool operator <(ResultSave left,ResultSave right) => left.CompareTo(right) < 0;
    [global::System.Runtime.CompilerServices.MethodImpl(global::System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
    public static bool operator >(ResultSave left,ResultSave right) => left.CompareTo(right) > 0;
    [global::System.Runtime.CompilerServices.MethodImpl(global::System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
    public static bool operator <=(ResultSave left,ResultSave right) => left.CompareTo(right) <= 0;
    [global::System.Runtime.CompilerServices.MethodImpl(global::System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
    public static bool operator >=(ResultSave left,ResultSave right) => left.CompareTo(right) >= 0;

    [global::System.Runtime.CompilerServices.MethodImpl(global::System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
    public readonly override string ToString() => this.Tag switch
    {
        Tags.Ok => $"{nameof(ResultSave)}.{nameof(Tags.Ok)} {{ {this.Ok} }}",
        Tags.NotFound => $"{nameof(ResultSave)}.{nameof(Tags.NotFound)}",
        _ => nameof(ResultSave),
    };
}

} // namespace UnionTypesDemo

Code and pdf at

https://ignatandrei.github.io/RSCG_Examples/v2/docs/Sera.Union