Experiência do desenvolvedor e limitações

Visão geral de DX e limites

Nomes previsíveis

using System;

// Emulate "predictable" generated naming: suffixes and folders are consistent.
public partial class Order
{
  public int Id;
}

// Simulated generated piece: same partial name, with a clear suffix convention.
public partial class Order // would live in Order.g.cs typically
{
  public string DebugId()
  {
    // predictable member name makes discovery easy
    return "Order#" + Id;
  }
}

public class Program
{
  public static void Main(string[] args)
  {
    Order o = new Order();
    o.Id = 42;
    Console.WriteLine(o.DebugId());
  }
}

Como evitar conflitos

using System;

namespace Generated
{
  // Emulate a generator using a dedicated namespace to reduce collisions
  public static class OrderExtensions
  {
    public static string ToLabel(this Order o) { return "Order: " + o.Id; }
  }
}

public partial class Order { public int Id; }

public class Program
{
  public static void Main(string[] args)
  {
    Order o = new Order();
    o.Id = 7;
    // Extension lives under Generated.* to stay out of the way
    Console.WriteLine(Generated.OrderExtensions.ToLabel(o));
  }
}

Diagnósticos úteis

using System;

// Emulate generator diagnostics: validate inputs and print clear messages.
public static class GenCheck
{
  public static string EmitGetter(string fieldName)
  {
    if (string.IsNullOrEmpty(fieldName))
      return "DIAGNOSTIC: Field name is empty. Skipping emission.";
    if (!char.IsLetter(fieldName[0]))
      return "DIAGNOSTIC: Field must start with a letter: " + fieldName;

    // pretend emission was fine
    return "OK: Generated getter for " + fieldName;
  }
}

public class Program
{
  public static void Main(string[] args)
  {
    Console.WriteLine(GenCheck.EmitGetter("1bad")); // diagnostic
    Console.WriteLine(GenCheck.EmitGetter("name")); // ok
  }
}

Saídas pequenas e focadas

using System;

// Emulate small, single-purpose emissions instead of huge files.
public partial class Report
{
  public int Count;
}

public partial class Report // Report.Stats.g.cs idea
{
  public double Average(int total)
  {
    if (Count == 0) return 0.0;
    return (double)total / Count;
  }
}

public partial class Report // Report.Format.g.cs idea
{
  public string Summary(int total)
  {
    return "Total=" + total + ", Count=" + Count + ", Avg=" + Average(total);
  }
}

public class Program
{
  public static void Main(string[] args)
  {
    Report r = new Report();
    r.Count = 4;
    Console.WriteLine(r.Summary(20));
  }
}

Limites e alternativas

Boa prática de DX

Recapitulação