PASCAL: Strings

STRINGS
The following program illustrates using STRINGS (a sequence of characters) in a DG Pascal program. STRING is type defined as a packed array of type char.

Message is then declared as the same type as STRING, ie, a packed array of characters, elements numbered one to eight.


	PROGRAM DGSTRING (INPUT, OUTPUT);
	TYPE STRING = PACKED ARRAY [1..8] OF CHAR;
	VAR  MESSAGE : STRING;
	BEGIN
	        WRITELN('HELLO BRIAN.');
	        MESSAGE := '12345678';
	        WRITELN('THE MESSAGE IS ', MESSAGE)
	END.

Turbo Pascal, how-ever, allows an easier use of character strings by providing a new keyword called STRING. Using STRING, you can add a parameter (how many characters) specifying the string length. Consider the above program re-written for turbo pascal.


	PROGRAM TPSTRING (INPUT, OUTPUT);
	VAR  MESSAGE : STRING[8];
	BEGIN
	        WRITELN('HELLO BRIAN.');
	        MESSAGE := '12345678';
	        WRITELN('THE MESSAGE IS ', MESSAGE)
	END.

Obviously, the turbo pascal version is easier to use. BUT, the following program shows a similar implementation for use on the DG.


	PROGRAM DGSTRING2 (INPUT, OUTPUT);
	CONST   $STRINGMAXLENGTH = 8;         {defines maxlength of a string}
	%INCLUDE 'PASSTRINGS.IN';             {include code to handle strings}
	VAR  MESSAGE : $STRING_BODY;
	BEGIN
	        WRITELN('HELLO BRIAN.');
	        MESSAGE := '12345678';
	        WRITELN('THE MESSAGE IS ', MESSAGE)
	END.