Path: utzoo!attcan!uunet!aplcen!uakari.primate.wisc.edu!zaphod.mps.ohio-state.edu!sunybcs!acsu.buffalo.edu
From: volaski@acsu.buffalo.edu (maurice volaski)
Newsgroups: comp.sys.mac.programmer
Subject: THINK PASCAL's Observe not working right?!
Message-ID: <15719@eerie.acsu.Buffalo.EDU>
Date: 12 Jan 90 18:08:05 GMT
Sender: nobody@acsu.Buffalo.EDU
Organization: SUNY at Buffalo
Lines: 51

Below is a program written in THINK Pascal that performs the 
Macintosh's famous task of command-period to cancel. The programs 
loops idly until command-period is pressed and then it quits.

However, according to one aspect of THINK Pascal's debugger it 
shouldn't work. In the Lightsbug window, the variables are updated 
properly, but in the Observe window they are not. The variable temp 
is appropriately set to true when command-period is set to true, but 
the the function result CmdPeriod is not set to the value of temp!
This only occurs in the observe window, not anywhere else. 
Anyone familiar with problems like this one and others in THINK Pascal's 
Observe window? Rich Siegal, are you listening?

program testcmdperiod;
 var
  BtnUpdate: boolean;

 function CmdPeriod: boolean;
  const
   periodKey = 46;
  var
   chCode: integer;
   stopEvent: EventRecord;
   temp: boolean;
 begin
  CmdPeriod := false;
  if GetNextEvent(keyDownMask, stopEvent) then
   begin
    with stopEvent do
     begin
     if (BitAnd(modifiers, CmdKey) <> 0) and 
		(BitAnd(message, CharCodeMask) = periodKey) then
      temp := true
     else
      temp := false;
     end;
   end
  else
   temp := false;
  CmdPeriod := temp;		{This line doesn't work according to only Observe}
 end;

begin
 BtnUpdate := false;
 repeat
  begin
   ;
  end;
 until CmdPeriod;
 BtnUpdate := true;
end.