c# - 在 C# 中编写我的第一个 DSL 并挂断了 func & Action

Question

我正在努力为工作中的一个简单工具编写我的第一个 DSL。我正在使用构建器模式来设置复杂的父对象，但在构建父对象的子集合时遇到了障碍。这是一个示例:

使用:

var myMorningCoffee = Coffee.Make.WithCream().WithOuncesToServe(16);

闭包示例(我想这就是它们的名称):

var myMorningCoffee = Coffee.Make.WithCream().PourIn( 
                        x => {
                                x.ShotOfExpresso.AtTemperature(100);
                                x.ShotOfExpresso.AtTemperature(100).OfPremiumType();
                             }
                        ).WithOuncesToServe(16);

示例类(没有子 PourIn() 方法，因为这是我想要弄清楚的。)

 public class Coffee
 {
   private bool _cream;

   public Coffee Make { get new Coffee(); }
   public Coffee WithCream()
   {
     _cream = true;
     return this;
   }
   public Coffee WithOuncesToServe(int ounces)
   {
     _ounces = ounces;
     return this;
   }
 }

所以在我的工作应用程序中，我可以很好地构建复杂的对象，但我终究无法弄清楚如何为父对象的子集合编码 lambda。 (在这个例子中是 expresso 的镜头(子集合))。

也许我在这里混淆了概念，但我不介意直截了当；但是，我真的很喜欢它的阅读方式，并想弄清楚如何让它发挥作用。

谢谢，山姆

Answer 1

好的，所以我想出了如何使用额外的表达式构建器来编写我的 DSL。这就是我希望我的 DSL 阅读的方式:

var myPreferredCoffeeFromStarbucks =
            Coffee.Make.WithCream().PourIn(
                x =>
                    {
                        x.ShotOfExpresso().AtTemperature(100);
                        x.ShotOfExpresso().AtTemperature(100).OfPremiumType();
                    }
                ).ACupSizeInOunces(16);

这是我通过的测试:

[TestFixture]
public class CoffeeTests
{
    [Test]
    public void Can_Create_A_Caramel_Macchiato()
    {
        var myPreferredCoffeeFromStarbucks =
            Coffee.Make.WithCream().PourIn(
                x =>
                    {
                        x.ShotOfExpresso().AtTemperature(100);
                        x.ShotOfExpresso().AtTemperature(100).OfPremiumType();
                    }
                ).ACupSizeInOunces(16);

        Assert.IsTrue(myPreferredCoffeeFromStarbucks.expressoExpressions[0].ExpressoShots.Count == 2);
        Assert.IsTrue(myPreferredCoffeeFromStarbucks.expressoExpressions[0].ExpressoShots.Dequeue().IsOfPremiumType == true);
        Assert.IsTrue(myPreferredCoffeeFromStarbucks.expressoExpressions[0].ExpressoShots.Dequeue().IsOfPremiumType == false);
        Assert.IsTrue(myPreferredCoffeeFromStarbucks.CupSizeInOunces.Equals(16));
    }
}

这是我的 CoffeeExpressionBuilder DSL 类:

public class Coffee
{
    public List<ExpressoExpressionBuilder> expressoExpressions { get; private set; }

    public bool HasCream { get; private set; }
    public int CupSizeInOunces { get; private set; }

    public static Coffee Make
    {
        get
        {
            var coffee = new Coffee
                             {
                                 expressoExpressions = new List<ExpressoExpressionBuilder>()
                             };

            return coffee;
        }
    }

    public Coffee WithCream()
    {
        HasCream = true;
        return this;
    }

    public Coffee ACupSizeInOunces(int ounces)
    {
        CupSizeInOunces = ounces;

        return this;
    }

    public Coffee PourIn(Action<ExpressoExpressionBuilder> action)
    {
        var expression = new ExpressoExpressionBuilder();
        action.Invoke(expression);
        expressoExpressions.Add(expression);

        return this;
    }

    }

public class ExpressoExpressionBuilder
{
    public readonly Queue<ExpressoExpression> ExpressoShots = 
        new Queue<ExpressoExpression>();

    public ExpressoExpressionBuilder ShotOfExpresso()
    {
        var shot = new ExpressoExpression();
        ExpressoShots.Enqueue(shot);

        return this;
    }

    public ExpressoExpressionBuilder AtTemperature(int temp)
    {
        var recentlyAddedShot = ExpressoShots.Peek();
        recentlyAddedShot.Temperature = temp;

        return this;
    }

    public ExpressoExpressionBuilder OfPremiumType()
    {
        var recentlyAddedShot = ExpressoShots.Peek();
        recentlyAddedShot.IsOfPremiumType = true;

        return this;
    }
}

public class ExpressoExpression
{
    public int Temperature { get; set; }
    public bool IsOfPremiumType { get; set; }

    public ExpressoExpression()
    {
        Temperature = 0;
        IsOfPremiumType = false;
    }
}

欢迎提出任何建议。