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   Line Labels:
     Line labels in Pascal must be defined prior to use.  There is
     no such thing as a return, like in TAS.  Also, Line labels
     defined within a procedure are exclusive to that procedure
     program labels (input,output);
     label 1,2;
     uses crt;
     var pick:char;
     procedure first;
       label 1,2;
       begin             {begin first}
       1:writeln ('This is the beginning of the subroutine');
         write ('do you wish to goto the end of 
                 the subroutine? (y/n) ');
         pick := readkey;
         case (pick) of 
            'y','Y':goto 2
             goto 1;
        2:end;               {end first}
      begin      {main program}
      1: writeln ('this is beginning of the main program');
         write ('Do you want to skip subroutine first (y/n): ');
         pick := readkey;
         case pick of
                       goto 1;
                goto 2;
       2: end.

Command: (procedure) Commands/Procedures do the same as a TAS subroutine. values may be passed to either one, TAS or Pascal. Procedures may only call Procedures that are coded ABOVE the current procedure. EXAMPLE program commands (input,output); var a,b:integer; procedure values; var a,b:integer; begin a:=15; b:=10; writeln (a,b); end; begin a:=10; b:=15; writeln(a,b); values; end.
Functions: Functions in Pascal are much the same as in TAS, but you have to define the type of variable that is retured by the function. EXAMPLE program (input,output); var x,answer:integer function square(x:integer):integer; begin square := x*x; end; begin writeln ('please enter the number to be squared'); readln (x); answer := square(x); end.
Control Structures: Re: CS's Pascal and TAS are similar. TAS has a database loop which Pascal completely lacks. In Pascal CS's must be blocked off with a begin and end, if not, it will only execute the ONE line of code beneath it, and continue on to the next after execution. EXAMPLE while (a < b) do begin writeln(a); a:=a+1; end;
for cntr:= 1 to 15 do begin {Note that we could take out the} { begin and end, and this would} writeln(cntr); { still work} end;
{in repeat/until commands they are already blocked off} { a begin and end are not needed.} cntr := 1; repeat writeln (cntr); cntr := cntr + 1 until (cntr > 15)
case (cntr) of 1..3:writeln ('cntr was one, two or three.'); 4:begin writeln('cntr was 4.'); writeln('extra statement'); end; else writeln ('wasn''t 1, 2, 3 or 4'); end; {end of case statemen}
a:=7; b:=8; if a > b then begin {note: where the begin is} {placed isn't important} writeln ('a is greater than b'); end else if b > a then begin writeln ('b is greater than a'); end else begin writeln ('they are equal'); end;
INPUTTING VALUES: In Pascal you don't have the ability to control the input as easily as TAS. You cannot default or use arrows to move from input to input. EXAMPLE var x:integer; begin writeln ('Please enter a number'); readln (x); end.
Outputs: There are only two ways to output in Pascal the only difference between the two being the carriage return. EXAMPLE write ('This is a test'); {This will print "this is a test"} {leaveing te cursor at the end of} {the output. } writeln ('This is a test'); {This will output the same thing} {except it will go down to the } {next line of current window. }
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