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Troubleshooting

"Type must be partial"​

error CS0260: Missing partial modifier on declaration of type 'Money'
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Add partial to your type declaration:

// Wrong
[ValueObject]
public class Money { ... }

// Correct
[ValueObject]
public partial class Money { ... }

Generated code not appearing​

  1. Ensure the ZeroAlloc.ValueObjects NuGet package is installed (not just referenced as a project without the correct metadata)
  2. Rebuild the project (Build → Rebuild Solution or dotnet build)
  3. In Visual Studio, check Analyzers under the project's Dependencies node to confirm the generator is loaded
  4. Verify the type is partial and the attribute namespace is ZeroAlloc.ValueObjects

Equality not working as expected​

If == returns false for two objects you expect to be equal, check:

1. Are the right properties included?

Use [EqualityMember] to be explicit:

[ValueObject]
public partial class Product
{
    [EqualityMember] public string Sku { get; }
    [EqualityMember] public string Name { get; }
    // Other props excluded
}

2. Are properties normalized in the constructor?

If one value is "USD" and another is "usd", they are not equal. Normalize in the constructor:

public Money(decimal amount, string currency)
{
    Amount = amount;
    Currency = currency.ToUpperInvariant();  // normalize
}

3. Are nested reference-type properties using value equality?

If a property is itself a class without overridden equality, the generated comparison falls back to reference equality. Ensure nested types also use [ValueObject] or otherwise implement value equality.

[ValueObject]
public partial class Shipment
{
    public Money Cost { get; }      // Money also has [ValueObject] — uses its Equals()
    public string Carrier { get; }
}

ToString output is not what I want​

The generated ToString follows the record convention: TypeName { Prop1 = val1, Prop2 = val2 }. Override it in your partial declaration:

[ValueObject]
public partial class Money
{
    public decimal Amount { get; }
    public string Currency { get; }

    // Overrides the generated version
    public override string ToString() => $"{Amount:F2} {Currency}";
}

Struct is generated as a class (or vice versa)​

Check the ForceClass property:

  • [ValueObject] on a partial struct → generates readonly partial struct
  • [ValueObject(ForceClass = true)] on a partial struct → generates sealed partial class
  • [ValueObject] on a partial class → generates sealed partial class

Compiler warning: CS0659 or CS0661​

These warnings appear when you override only one of Equals/GetHashCode or only operator ==/operator !=. They should not occur with the generator since it always emits the full set. If you see them, check that you haven't added a partial Equals or GetHashCode that conflicts with the generated one.