====== The Pascal Compiler ======

The TWENEX.ORG Pascal compiler was originally developed at the
University of Hamburg as "DECSystem-10 Pascal". The compiler was
later modified and distributed by Rutgers University with fixes
and updates contributed by CMU, Stanford, USC, Sandia National
Laboratories and other sites.

The compiler can be invoked either with the [[tutorials:compilers|standard compile/load/execute commands]] or directly with the EXEC command ''PASCAL''. The standard extension for Pascal source files is ''.PAS''.

===== Hello, World! =====

To create and run a //Hello, World!// program in Pascal:

<code>
[KANKAN] PUBLIC:<~>@ create hello.pas
</code>

Your default text editor will start. Enter and save the following:

<code>
(* Hello program in Pascal *)

program Hello (Output);
begin
	writeln ('Hello, World!');
end.
</code>

Return to EXEC then compile and run the program:

<code>
[KANKAN] PUBLIC:<~>@ execute hello
PASCAL:	HELLO
LINK:	Loading
[LNKXCT	HELLO execution]
OUTPUT     : 
Hello, World!
[KANKAN] PUBLIC:<~>@ 
</code>

  * Syntax of the EXECUTE command is ''EXECUTE //filename//[.//extension//]''. The file extension is optional if you used the standard source file extension (''.PAS'') and there are no other program source files with the same name in your default directory.
  * At the ''OUTPUT     :'' prompt, press ''Enter'' to direct output to your terminal.

===== Additional Information =====

Additional information on the Pascal compiler can be found in ''HELP PASCAL''. (The help file mentions a second Pascal compiler, PASSGO, which is not available on TWENEX.ORG.) Additional documentation is in the following files in directory ''NEO:<DOCUMENTATION>'' (''DOC:''):
  * PASCAL.DOC
  * PASCAL.HACKER
  * PASCAL.INCOMPATIBILITIES-DOC
  * PASCAL.MEM
  * PASCAL.UPDATE
  * PASCAL.USER

The following is a reference on the ISO Pascal language standard:

  * K. Jensen and N. Wirth, //[[http://pascal.hansotten.com/uploads/books/Pascal_User_Manual_and_Report_Fourth_Edition.pdf|Pascal User Manual and Report, 4th ed.]]// New York: Springer-Verlag, 1991. [Accessed: 2024/6/20]