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Delphi 有许多记录在案的运算符重载：

用于记录和ARC_classes（在 NexGen 编译器中）。
正式地，它不支持类、接口或简单类型的运算符重载。

除了...

有一些未记录的运算符重载确实适用于接口、类和简单类型。
（尽管无证操作员似乎不处理记录）。

例如，以下代码将编译并工作：

Win32/64 中类的运算符重载 

//sorry for the horrible use of `or` to use for nil testing.
//I'd code this into a function (function FirstAssigned(a,b: TObject): TObject;
//It's just an example to demonstrate the concept. 
type
  TObjectHelper = class helper for TObject
  public
    class function &&op_LogicalOr<T: class>(A, B: T): T; static;
  end;

class function TObjectHelper.&&op_LogicalOr<T>(A, B: T): T;
begin
  if A <> nil then
    Result := A
  else
    Result := B;
end;

procedure Test;
var
  sl1, sl2, sl3: TStringList;
begin
  sl1 := nil;
  sl2 := TStringList.Create;
  sl3 := sl1 or sl2; // -> sl3 = sl2
end;

作为参考，这里列出了所有允许的运算符：

运营商名单 

class operator      class function          example
---------------------------------------------------
Implicit            &&op_Implicit           x:= y;
Explicit            &&op_Explicit           x:= integer(y);
Negative            &&op_UnaryNegation      x:= -y
Positive            &&op_UnaryPlus          x:= +y
Inc                 &&op_Increment          Inc(x);
Dec                 &&op_Decrement          Dec(y);
LogicalNot          &&op_LogicalNot         Not(y); //can be used for bitwise not as well
Trunc               &&op_Trunc              i:= trunc(f);
Round               &&op_Round              i:= round(f);
In                  &&op_In                 if (i in s) then
Equal               &&op_Equality           a = b
NotEqual            &&op_Inequality         a <> b
GreaterThan         &&op_GreaterThan        a > b
GreaterThanOrEqual  &&op_GreaterThanOrEqual a >= b 
LessThan            &&op_LessThan           a < b
LessThanOrEqual     &&op_LessThanOrEqual    a <= b
Add                 &&op_Addition           a + b
Subtract            &&op_Subtraction        a - b
Multiply            &&op_Multiply           a * b
Divide              &&op_Division           a / b //floating point div
IntDivide           &&op_IntDivide          a div b //integer div
Modulus             &&op_Modulus            a mod b
LeftShift           &&op_LeftShift          a shl b
RightShift          &&op_RightShift         a shr b
LogicalAnd          &&op_LogicalAnd         if (a and b) then ...
LogicalOr           &&op_LogicalOr          if (a or b) then ....
LogicalXor          &&op_ExclusiveOr        if (a xor b) then
BitwiseAnd          &&op_BitwiseAnd         x:= a and b
BitwiseOr           &&op_BitwiseOr          x:= a or b
BitwiseXor          &&op_BitwiseXOR         x:= a xor b
Include             &&op_Include            include(s, i);
Exclude             &&op_Exclude            exclude(s, i);

将这些重载与（非弧）类一起使用时，如何避免遇到内存泄漏？

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