[Thor]

This is how to do it...
/Thor

program Project1;

{$APPTYPE CONSOLE}

uses
  SysUtils;

type
  TFunctionPtr = function (P1: integer) : string;

function MyFunction(P1: integer): string;
begin
  result := IntToStr(P1);
end;

procedure Caller(Func: TFunctionPtr; Version: integer);
begin
  Writeln('My current Delphi version = ' + Func(Version));
end;

begin
  Caller(MyFunction, 10);
  Readln;
end.