Delphi – E2080 Procedure DISPOSE needs destructor

Posted by AbundantCode

This error message is displayed when one of the identifiers in the Dispose parameter list is not a destructor.

program Produce;

type
  PMyObject = ^TMyObject;
  TMyObject = object
  F: Integer;
  constructor Init;
  destructor Done;
  end;

constructor TMyObject.Init;
begin
  F := 42;
end;

destructor TMyObject.Done;
begin
end;

var
  P: PMyObject;

begin
  New(P, Init);
  (*...*)
  Dispose(P, Init);        (*<-- Error message here*)
end.

The constructor was accidentally passed to Dispose in this example.

program Solve;

type
  PMyObject = ^TMyObject;
  TMyObject = object
  F: Integer;
  constructor Init;
  destructor Done;
  end;

constructor TMyObject.Init;
begin
  F := 42;
end;

destructor TMyObject.Done;
begin
end;

var
  P: PMyObject;

begin
  New(P, Init);
  Dispose(P, Done);
end.

Either supply a destructor to Dispose or remove the second argument as a solution.

Tags: