Purview.ValueObjects 1.0.0-prerelease.6

Purview.ValueObjects

Source-generated scalar and complex value objects for .NET.

Adds F#-style single-case types to C#. Mark a partial struct or class with [Scalar] or [ValueObject] and the source generator produces Create/Hydrate factories, normalization (OnNormalize), validation (OnValidate), Empty instances, equality, comparison, implicit conversions, and JSON converters.

• DTOs – strong types with serialization/deserialization and business rules.
• Entity Framework – reference Microsoft.EntityFrameworkCore and the generator emits mapping members (value converters, comparers, complex-type mapping) plus a ConfigureValueObjects extension for automatic mapping. Queries use the value object type directly.
• Domain models – the F#-style single-case union pattern in C#.

Quick start

[Scalar]
public readonly partial record struct EmailAddress
{
    public string Value { get; }

    static partial void OnNormalize(ref string value) => value = value?.Trim().ToLowerInvariant()!;

    static partial void OnValidate(string value)
    {
        if (string.IsNullOrWhiteSpace(value))
            throw new ArgumentException("Email is required.", nameof(value));
    }
}

var email = EmailAddress.Create("Demo@Example.com");
// email.Value == "demo@example.com"

JSON serialization

Scalar value objects serialize as their underlying value. Register the converter factory on your JsonSerializerOptions:

var options = new JsonSerializerOptions();
options.Converters.Add(new ScalarJsonConverterFactory());

Use the same options for Entity Framework JSON columns:

modelBuilder
    .Entity<Customer>()
    .Property(c => c.Email)
    .HasColumnType("jsonb");

Entity Framework Core

When your project references Microsoft.EntityFrameworkCore, the generator emits an EF nested class per value object (a ValueConverter/ValueComparer) and an assembly-level ConfigureValueObjects extension that maps them automatically:

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    modelBuilder.ConfigureValueObjects();   // generated into your project
}

Scalar value objects convert to their underlying primitive column; complex value objects map as EF Core complex types (EF Core 8+) by default or JSON columns via [ValueObject(EFMapping = EntityFrameworkMapping.Json)]. Queries compare the value object type directly — no .Value required — or the raw underlying value (c.Email == "...", m.Id == guid). See docs/Entity-Framework.md for the full guide.

See the src/src/Sample and src/src/ZodSharpSample projects for end-to-end examples.