Why does Rider suggests me to use deconstruction?

Question

I'm writing this class:

private class SameCellsComparer : EqualityComparer<Links> 
{
    public override bool Equals(Links t1, Links t2)
    {
        return t1 == null || t1.Equals(t2);
    }
    public override int GetHashCode(Links t)
    {
        // we suppose there will always be less than 100 000 000 items:
        return t.Item1.id + t.Item2.id * 100000000;
    }
}

But Rider suggests me to use deconstruction on GetHashCode(Links t), and if I apply the suggestion, I get this:

private class SameCellsComparer : EqualityComparer<Links> 
{
    public override bool Equals(Links t1, Links t2)
    {
        return t1 == null || t1.Equals(t2);
    }
    public override int GetHashCode(Links t)
    {
        // we suppose there will always be less than 100 000 000 items:
        (Cell item1, Cell item2) = t;
        return item1.id + item2.id * 100000000;
    }
}

Please don't talk about doing bad GetHashCode() principle, I'm only asking for the conversion to (Cell item1, Cell item2) = t: is it safer, faster, cleaner? I don't get it.

Answer 1

That is just a syntax sugar. With deconstruction you can control the name of the tuple items.

Check this gist I created.

For this C# code:

using System;
public class C {
    public void M() {
        (string fff,String fff2) = C.Do();
        
        var l = C.Do();
    }
    
   public static (String a, String b) Do(){
       return ("aaa", "bvvvv");
   }
}

Compiler see it like this:

using System;
using System.Diagnostics;
using System.Reflection;
using System.Runtime.CompilerServices;
using System.Security;
using System.Security.Permissions;

[assembly: CompilationRelaxations(8)]
[assembly: RuntimeCompatibility(WrapNonExceptionThrows = true)]
[assembly: Debuggable(DebuggableAttribute.DebuggingModes.Default | DebuggableAttribute.DebuggingModes.DisableOptimizations | DebuggableAttribute.DebuggingModes.IgnoreSymbolStoreSequencePoints | DebuggableAttribute.DebuggingModes.EnableEditAndContinue)]
[assembly: SecurityPermission(SecurityAction.RequestMinimum, SkipVerification = true)]
[assembly: AssemblyVersion("0.0.0.0")]
[module: UnverifiableCode]
public class C
{
    public void M()
    {
        ValueTuple<string, string> valueTuple = Do();
        string item = valueTuple.Item1;
        string item2 = valueTuple.Item2;
        ValueTuple<string, string> valueTuple2 = Do();
    }

    [return: TupleElementNames(new string[] {
        "a",
        "b"
    })]
    public static ValueTuple<string, string> Do()
    {
        return new ValueTuple<string, string>("aaa", "bvvvv");
    }
}

Notice that this lines:

  ValueTuple<string, string> valueTuple = Do();
        string item = valueTuple.Item1;
        string item2 = valueTuple.Item2;
        ValueTuple<string, string> valueTuple2 = Do();

Are approximately the same code.