为什么不提高 EInvalidPointer？

Question

Never raise an EInvalidPointer exception directly. EInvalidPointer is raised internally by the memory manager.

我正在编写自定义基础 class 作为 TInterfacedObject 的替代方案，尽可能遵循 RTL 实现，并通过示例查看 TInterfacedObject 在RTL 将 BeforeDestruction 实现为：

procedure TInterfacedObject.BeforeDestruction;
begin
  if RefCount <> 0 then
    Error(reInvalidPtr);  
end;

其中 Error(reInvalidPtr) 通过 RTL 本地的各种单元范围方法引发 EInvalidPointer。

如果我自己编写 class，我应该如何实现 BeforeDestruction？为什么不这样做呢？ :

procedure TMyInterfacedObject.BeforeDestruction;
begin
  if RefCount <> 0 then
    raise EInvalidPointer.CreateRes(@SInvalidPointer) at ReturnAddress;
end;

在SysUtils中声明的全局InvalidPointer异常对象有什么特别之处吗？如果这是一个坏主意，那么在这里简单地引发自定义异常是否明智？

Answer 1

回避原问题，只需使用与运行时相同的代码即可避免提问：

System.Error(reInvalidPtr);

Answer 2

对; what's special about InvalidPointer, which is used to raise an EInvalidPointer, together with OutOfMemory <-> EOutOfMemory is explained in more detail in the documentation topic for their ascendant EHeapException的补充：

EHeapException is the exception class for errors related to heap-allocated memory.

EHeapException's descendants—EOutOfMemory and EInvalidPointer—are used to handle failed allocations of dynamic memory and invalid pointer operations.

Note: Memory for these exceptions is pre-allocated whenever an application starts and remains allocated as long as the application is running. Never raise EHeapException or its descendants directly.

我想这相当于，一旦内存出现问题，分配内存来创建这些错误可能是不安全的：因为缺少内存或可能损坏...

为什么不提高 EInvalidPointer？

Why not raise EInvalidPointer?

delphi

invalid-pointer