Visual Prolog?

Appeared in Volume 7/2, May 1994

Keywords: visual programming.


joerg@iolo.harvard.edu 
David "S." Joerg
24th January 1994

I was wondering if there are any academic or commercial visual LP languages and/or development environments.


spratt@hawk.cs.ukans.edu
Lindsey Spratt
25th January 1994

I am working on a visual LP language based on sets and partitioning constraints (which I currently call SPARCL) for my PhD research. I presented a brief paper on this, "A Visual Logic Programming Language Based on Sets and Partitioning Constraints." by Lindsey Spratt (myself) and Allen Ambler (my advisor), at the IEEE Symp. on Visual Languages in Bergen, Norway, in June of 1993.

Below is the visual LP languages discussion in the "related work" section of my dissertation proposal, which gives my understanding of the state of the art. (One additional note, someone told me that the CUBE language is now being implemented using LDL. Since LDL handles sets explicitly, does this mean that CUBE will handle sets visually?)

Visual programming languages that have logic programming paradigm semantics include: "Predicates and Pixels" [1], CUBE [2], Pictorial Janus [3], VLP [4], VPP [5], Mpl [6] (which is actually a constraint logic language, based on CLP(R) [7]), and picture LP [8].

Of the various kinds of visual languages, the visual logic languages are of most interest to the SPARCL project. They differ importantly from SPARCL in that none of them make use of sets (or partitions of sets). Also, they have very limited or nonexistent meta-programming capabilities. Only CUBE and Pictorial Janus are completely visual environments; the others rely on linear textual presentations of code in certain situations. Mpl is a combination of a straight linear textual Prolog plus a two- dimensional presentation of matrices, intermingled in the linear presentation. Mpl introduces novel pattern matching techniques for matrices which may have some analog in SPARCL.

There has been some work in visualizing logic programs, which is distinct from a visual programming language. The Transparent Logic Machine (TLM) [9] and the AND/OR graph-based system of Senay and Lazzeri [10] are examples of this. TLM offers another approach to representing logic graphically which may be useful to SPARCL.

In a somewhat different vein, Peirce presented a diagrammatic representation of logic. He proposed this as an alternative to linear textual representation of first order logic. John Sowa proposed a diagrammatic representation for higher order logic, conceptual graphs, in [11]. There is a current effort to implement a system which uses Peirce's diagrammatic logic in conjunction with Sowa's. This system is more of a theorem proving environment than a programming language environment.

Bibliography

[1] Ringwood 1989 "Predicates and Pixels" by G. Ringwood in New Generation Computing, 7, 1989, pp. 59-70.

[2] "The CUBE Language" by Marc A. Najork and Simon M. Kaplan. Pages 218 to 224 in Proceedings of the 1991 IEEE Workshop on Visual Languages, October 8-11, 1991, Kobe, Japan. IEEE Computer Society Press:Los Alamitos, CA. 1991.

[3] "Complete Visualizations of Concurrent Programs and their Executions" by Kenneth M. Kahn and Vijay A. Saraswat. Pages 7 to 15 in Proceedings of the 1990 IEEE Workshop on Visual Languages, October 4-6, 1990, Skokie, Illinois. IEEE Computer Society Press: Los Alamitos, CA. 1990.

[4] "VLP: A Visual Logic Programming Language" by Dider Ladret and Michel Rueher in Journal of Visual Languages and Computing (1991) 2, 163-188.

[5] "Visual Logic Programming" by L. F. Pau and H. Olason in Journal of Visual Languages and Computing (1991) 2, 3-15.

[6] "Mpl - a graphical programming environment for matrix processing based on logic and constraints" by Ricky Yeung, in IEEE Workshop of Visual Languages, pages 137- 143. IEEE Computer Society Press, October 1988.

[7] "The CLP(R) Programmer's Manual", Version 1.2 by Nevin C. Heintze, Joxan Jaffar, Spiro Michaylov, Peter J. Stuckey, and Roland H. C. Yap. This manual is distributed with version 1.2 of CLP(R) by Joxan Jaffar at the IBM Thomas J. Watson Research Center. This manual is dated September 1992.

[8] "Pictures Depicting Pictures: On the Specification of Visual Languages by Visual Grammars" by Bernd Meyer. Pages 41-47 in Proceedings of the 1992 IEEE Workshop on Visual Languages September 15-18, 1992, Seattle, Washington. IEEE Computer Society Press:Los Alamitos, CA. 1992.

[9] "The Transparent Prolog Machine (TPM): an execution model and graphical debugger for LP" by M. Eisenstadt and M. Brayshaw. In Journal of Logic Programming, 5 (4), 1988.

[10] "Graphical Representation of Logic Programs and Their Behavior" by Hikmet Senay and Santos G. Lazzeri. Pages 25 to 31 in Proceedings of the 1991 IEEE Workshop on Visual Languages, October 8-11, 1991, Kobe, Japan. IEEE Computer Society Press:Los Alamitos, CA. 1991.

[11] "Conceptual Structures - Information Processing in Mind and Machine" by John A. Sowa. Reading MA: Addison-Wesley. 1984.


alanw@cix.compulink.co.uk 
Alan Westwood
25th January 1994

We (LPA) have a visual programming tool called MacObject that runs under MacProlog and enables the graphical design of Prolog++ (Object Oriented Prolog extension) programs. For more information, contact: Clive Spenser Marketing Director Email lpa@cix.compulink.co.uk


popx@vax.oxford.ac.uk
Jocelyn Paine
25th January 1994

David "S." Joerg writes:

I was wondering if there are ANY academic or commercial projects

Yes, it was described in a volume of 1993 LP proceedings, near the end, in a one-page reprint of one of the posters in the conference's poster session. The title was something like 'A visual logic for spatial reasoning'.

The idea is that you write standard Prolog code, but you can have 'picture terms' as well as ordinary terms.

The researchers had been investigating various classes of pictures. The first class they tried was too general to allow efficient unification, because the unification mechanism had to do an exhaustive search for subgraph isomorphism between components of the pictures being unified. However, they've since defined a more restricted class of pictures which avoid this problem.


p.holmes-higgin@surrey.ac.uk
Paul Holmes-Higgin
25th January 1994

I'm aware of visual programming languages, but what I'd really like is a Prolog version of MS's Visual Basic as a development environment, not just a tool for designing GUIs and simply linking to Prolog. Is anyone doing this?


jan@swi.psy.uva.nl 
Jan Wielemaker
27th January 1994

More of less. I'm working on an environment that lets you graphically build a GUI and define the behaviour of this GUI. This is running on top of XPCE (ProWindows-3). While defining the behaviour, the behaviour-diagram is interpreted to generate the behaviour of the GUI. (Graphical) links can be made to Prolog predicates to be called by the interface. The environment will define a clause-skeleton (including arguments) which you may then further refine.

When completed, you simply drag the interface to the source-editor and it will insert the Prolog code to generate the interface.


fuchs@ifi.unizh.ch
Norbert E. Fuchs
27th January 1994

Markus Fromherz, a PhD student of mine, developed graphical editors for designing finite state machines and window-oriented user interfaces that were translated to and from an object-oriented extension of Prolog.


p.holmes-higgin@surrey.ac.uk
Paul Holmes-Higgin
10th February 1994

XPCE has just gained a new tool, still under beta test, for defining dialog boxes. It has drag and drop drawing of buttons, menus, edit items etc., with popup refinements on each dialog item; drag the dialog window name to an editor and it dumps the specification in Prolog source. The tool is called Visual Prolog.

What makes it really interesting is its behaviour editor. Drag the dialog items to this and you can define the functional interaction of the dialog boxes and their callbacks to Prolog. "Run" the behaviour model, do something in the dialog box - then watch the process run visually.


jan@swi.psy.uva.nl
Jan Wielemaker
11th February 1994

For those unfamiliar with XPCE, here is a short description.

XPCE is a generic GUI library for symbolic languages and C++ (although the Prolog environment is superior to the Lisp and C++ ones). It provides support for dialog windows, graphics (notably support for graphical diagramming languages and direct- manipulation graphics), text manipulation (there is PceEmacs written in XPCE/Prolog that can be extended in Prolog), interprocess and network communication, etc.

Most of the documentation is available under anonymous FTP from:
ftp://swi.psy.uva.nl/pub/xpce

XPCE runs on a number of Unix machines: SunOs 4.1.x and 5.[23], AIX 3.2, IRIX and Linux are well maintained, Ultrix and HP-UX may be a bit rusty.

XPCE was connected to SWI-Prolog originally, and later to SICStus and Quintus Prolog. The latter version is commercially distributed as ProWindows-3 and supported. It is available from AIIL (uk), who can be contacted at: sheywood@aiil.co.uk

Unsupported academic versions are available from SWI. The licence form and ordering info is on the ftp server. If you don't have ftp, contact: xpce-request@swi.psy.uva.nl.

A free (binary only) demo version is available for the PC/Linux platform from the ftp server (pub/xpce/linux). To be of any use, you need at least 8 MB on your Linux box and 33Mhz 486 or up. Using a 66DX2 and 16 MB it runs like a dream.

The Visual Prolog beta code is integrated in the academic and demo distribution. It will be distributed as a demonstration-tool in the next ProWindows-3 release.