I know you can use Labels in Basic, and I think C++, but can you use them in pascal?

In basic, you would use:

LabelX:
//code
if a = 5 then
GOTO LabelX;
end

If there are labels (Surely there are, right?) how would you use them?

This message was edited by Opius at 2003-2-24 16:15:50

---

: I know you can use Labels in Basic, and I think C++, but can you use them in pascal?
:
: In basic, you would use:
:

: LabelX:
: //code
: if a = 5 then
: GOTO LabelX;
: end
: 

:
: If there are labels (Surely there are, right?) how would you use them?
:


Labels/Goto statements are an integral part of spaghetti code. Fortunately (or unfortunately), there are no label/gotos in any strutctured programming language such as C++ or Pascal, at least as far as I know. An easy way to do this sort of thing is to use procedures and functions. Example

procedure RandomProcedureName(parameters);
   begin
      //code
   end;

begin
   //code
   if a=5 then
      RandomProcedureName(parameters);
end.

Functions operate in a similar way but must be used in an equation or output statement.

-Opius

: This message was edited by Opius at 2003-2-24 16:15:50

---

: : I know you can use Labels in Basic, and I think C++, but can you use them in pascal?
: :
: : In basic, you would use:
: :

: : LabelX:
: : //code
: : if a = 5 then
: : GOTO LabelX;
: : end
: : 

: :
: : If there are labels (Surely there are, right?) how would you use them?
: :
:
:
: Labels/Goto statements are an integral part of spaghetti code. Fortunately (or unfortunately), there are no label/gotos in any strutctured programming language such as C++ or Pascal, at least as far as I know. An easy way to do this sort of thing is to use procedures and functions. Example

Personally I havent ever used GOTO, but like everything there is a time and place for it. And Pascal does support it. Here is an example (written from memory, it may not be syntactically correct)

procedure Test;
label
  Bottom;
var
  Ch: Char;
begin
     while (1=1) do
     begin
          Ch := ReadKey;
          if (Ch = #27) then
             Goto Bottom;
     end;

:Bottom
     WriteLn('Used GOTO to exit the loop');     
end;

: I know you can use Labels in Basic, and I think C++, but can you use them in pascal?
:
: In basic, you would use:
:

: LabelX:
: //code
: if a = 5 then
: GOTO LabelX;
: end
: 

:
: If there are labels (Surely there are, right?) how would you use them?
:

Yep, you can. It's as easy as this:

USES Crt;
VAR
   Key : Char

LABEL VeryTop;

Begin
   VeryTop:
     WriteLn('Press a key...');
     ReadKey := Key;
     If UpCase(Key) <> 'Y' Then Goto VeryTop;
End.

Simple. Just decalre that before using them (Cannot be done in code section)

Phat Nat

This message was edited by Moderator at 2003-2-25 7:10:38

---

: I know you can use Labels in Basic, and I think C++, but can you use them in pascal?
:
: In basic, you would use:
:

: LabelX:
: //code
: if a = 5 then
: GOTO LabelX;
: end
: 

:
: If there are labels (Surely there are, right?) how would you use them?
:
Opius says in his post that labels help to create spaghetti code and that's correct. I would recommend learning to program without them. I started with Turbo Pascal 3.0 in 1984 and have never once used a label - goto. They're just not necessary. My$0.02

: This message was edited by Moderator at 2003-2-25 7:10:38

---

: : I know you can use Labels in Basic, and I think C++, but can you use them in pascal?
: :
: : In basic, you would use:
: :

: : LabelX:
: : //code
: : if a = 5 then
: : GOTO LabelX;
: : end
: : 

: :
: : If there are labels (Surely there are, right?) how would you use them?
: :
: Opius says in his post that labels help to create spaghetti code and that's correct. I would recommend learning to program without them. I started with Turbo Pascal 3.0 in 1984 and have never once used a label - goto. They're just not necessary. My$0.02

Yes and No. They aren't the greatest way of doing loops and in general you are right, they should be avoided, However, I recently used a GOTO statement in an emulator that I was creating. Since Emulation depends on speed and REPEAT UNTIL / WHILE DO statements always do some sort of check Even if it's something like: REPEAT UNTIL 1 = 2. although these would never be equal, it still would check first. By using a GOTO, you can skip the check step. That's the only place I've ever used one however. My $0.02

Phat Nat