Templates 奇怪的行为；这个T",；

有人能给我解释一下下面的行为吗

使用这样的基类：

abstract class Foo
{
    string[] members;

    final:

    this(this T)(T child)
    {
        import std.conv : to;

        foreach (member; __traits(derivedMembers, T))
        {
            mixin("members ~= to!string(child." ~ member ~ ");\r\n");
        }
    }

    void printMembers()
    {
        writeln(members);
    }
}

我希望用传递的子类型的值填充成员

然而，这种行为真的很奇怪

数组成员将无限填充，这基本上会导致程序内存不足

如果将mixin更改为：

mixin("if (members.length < 20) members ~= to!string(child." ~ member ~ ");\r\n");

上述代码将产生如下输出：

["1", "2", "1", "2", "1", "2", "1", "2", "1", "2", "1", "2", "1", "2", "1", "2", "1", "2", "1", "2", "f193.Bar", "f193.Bar", "f193.Bar", "f193.Bar", "f193.Bar", "f193.Bar", "f193.Bar", "f193.Bar", "f193.Bar"]
["100", "200", "300", "100", "200", "300", "100", "200", "300", "100", "200", "300", "100", "200", "300", "100", "200", "300", "100", "200", "f193.Baz", "f193.Baz", "f193.Baz", "f193.Baz", "f193.Baz", "f193.Baz"]
["1", "2", "1", "2", "1", "2", "1", "2", "1", "2", "1", "2", "1", "2", "1", "2", "1", "2", "1", "2", "f193.Bar", "f193.Bar", "f193.Bar", "f193.Bar", "f193.Bar", "f193.Bar", "f193.Bar", "f193.Bar", "f193.Bar"]

在那里，我本可以期待类似这样的事情：

["1", "2"]
["100", "200", "300"]
["1", "2"]

---

它到底为什么会这样？在我看来，这似乎是一个bug，但可能有这样的行为的原因？

看看我看到的代码，这是因为构造函数被称为递归

简单的修复方法如下所示：

static if (member != "__ctor") mixin("members ~= to!string(child." ~ member ~ ");\r\n"); 

static if (member != "__ctor") mixin("members ~= to!string(child." ~ member ~ ");\r\n");