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Path: utzoo!watmath!clyde!cbosgd!hplabs!sdcrdcf!ucla-cs!rms
From: rms@ucla-cs.UUCP
Newsgroups: net.cse
Subject: top-down editors and tracers for Pascal
Message-ID: <9859@ucla-cs.ARPA>
Date: Fri, 14-Mar-86 12:48:41 EST
Article-I.D.: ucla-cs.9859
Posted: Fri Mar 14 12:48:41 1986
Date-Received: Sat, 15-Mar-86 21:10:28 EST
Organization: UCLA Computer Science Department
Lines: 39

[This article is really from John Pedersen]

It seems that the frustrations students encounter in introductory
computing courses, and the large amounts of time spent by students
in these courses relative to others, might be decreased by two pieces
of software:

1) An intelligent editor, that not only helps students with syntax but
   also promotes top-down design/implementation and discourages bad
   style. After asking for the author's name, the program purpose etc.,
   the user has to type in the main program. The editor chides the user
   if it gets too long. When the user is finished, it checks the syntax
   and perhaps makes suggestions for improvement and can even foresee
   some logical problems (e.g. subscript out of range). It then looks
   for constants, variables and procedure/function calls, and puts in
   appropriate declarations in cooperation with the user. The editor
   automatically builds stubs for each proc/fn (that doesn't already
   exist). Then each subprogram body is treated in the same way in turn.
   The program can be run after each stage to see that the flow of
   control is as expected. The original user input for each block is not
   necessarily syntax-directed (the user gets a chance to make
   mistakes!)

2) A program tracing facility that shows the lines of source code as
   they are being executed (on one part of the screen) while variable
   and parameter values are given to the side. This is to help locate
   logical errors. Particular variables and/or subprograms can be
   isolated. This is different from a symbolic debugger in that the
   whole execution of the program can be seen "as it happens."

QUESTION: Do such tools already exist (or something close), specifically
	  for Pascal under Berkeley Unix (or System V)? I would greatly
	  appreciate hearing from you (by mail) if you know of or,
	  better yet, have experience with, such software, or if you
	  would be interested in using it for classes (if nothing exists
	  we might write it).
	
John Pedersen, Dept of Math., Program in Computing, UCLA, L.A. Ca. 90024
(213)825-1917   pic.jfp@LOCUS.UCLA.EDU    {ihnp4,ucbvax}!ucla-cs!pic.jfp