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Freeandnil - free memory for an object and set it to nil sysutils unit

procedure FreeAndNil ( var ObjectReference ) ; Description The FreeAndNil procedure frees up the memory used by an object, and sets the object reference to nil. It actually does this in reverse order - first dereferencing the object before deallocating the memory. This is a very clean way of freeing resources. Related commands FreeMem Free memory storage used by a variable GetMem Get a specified number of storage bytes Nil A pointer value that is defined as undetermined Null A variable that has no value Example code : Free and nil an object, and then try to do this again var myList : TList; begin // Create the list object myList := TList.Create; // And now free and nil this object FreeAndNil(myList); // We can safely do this twice - it ignores nil objects FreeAndNil(myList); end; Show full unit code No exception occurs - the second FreeAndNil does nothing.