Changing the variable that was used to push an item onto the stack changes the stack item itself.

The program is written in IDE lazarus 1.6. There is a class with this declaration:

DataForm = class public Choices:longint; BackUp:boolean; private nameForm:String; operationForm:TypeOperation; public function getForm():String; procedure setForm(const nForm:String); function getOperation():TypeOperation; procedure setOperation(const oForm:TypeOperation); end; 

And such a description:

 function DataForm.getForm():String; begin getForm:=nameForm; end; procedure DataForm.setForm(const nForm : String); begin nameForm:=nForm; end; function DataForm.getOperation():TypeOperation; begin getOperation:=operationForm; end; procedure DataForm.setOperation(const oForm:TypeOperation); begin operationForm:=oForm; end; 

To work with the stack from the class of such objects uses uses gstack;

 type iStack = specialize TStack<DataForm>; var TopForm: iStack; CurrentStatus:DataForm; 

In the form by pressing the button the following code is executed:

  TopForm.CleanupInstance; CurrentStatus.setForm('fRoot'); CurrentStatus.setOperation(oRoot); TopForm.Push(CurrentStatus); CurrentStatus.setForm('fViewPatientStory'); CurrentStatus.setOperation(View); TopForm.Push(CurrentStatus); CurrentStatus.setForm('fViewPatient'); CurrentStatus.setOperation(View); ShowMessage(TopForm.Top().getForm()); TopForm.Pop; ShowMessage(TopForm.Top().getForm()); 

Issued 2 messages: fViewPatient. I need the items pushed to the stack to remain with the same values ​​they were at the time of placement, and it turns out that any stack item refers to the CurrentStatus variable and when it changes, all values ​​of the stack items change. Please help.