I recently received the following Google Scholar alert for a “new” citation to my work:

“[HTML] page 2

S Woods, A Quilici, Q Yang

Different program understanding algorithms often use different representational 
frameworks and take advantage of numerous heuristic tricks. This situation makes it 
is difficult to compare these approaches and their performance. This paper 
addresses this problem by proposing constraint satisfaction as a general framework 
for describing program understanding algorithms, demonstrating how to tranform a 
relatively complex existing program understanding algorithm into an instance of a …”

“page 2” seemed rather an odd title for a paper. 🙂 Turns out it was not really a new citation, but seemed to refer to “page 2” of a 1995 tech report. But the tech report actually had a very intriguing title: Program Understanding: A Constraint Satisfaction Modeling Framework; Understanding as Plan Recognition.

I found a later related published work: Steven G. Woods, Qiang Yang: Program Understanding as Constraint Satisfaction: Representation and Reasoning Techniques. Autom. Softw. Eng. 5(2): 147-181 (1998).

And a whole book: Constraint-Based Design Recovery for Software Reengineering: Theory and Experiments. Woods, Steven G., Quilici, Alexander E., Qiang Yang.

Now I’m acquainted with Qiang Yang; we served on the AAAI Executive Council together. (Qiang was also President of IJCAI and General Chair of AAAI-21, among many other accomplishments.) I was curious why Qiang didn’t seem to have followed up on this intriguing work after 1998. Had it been a dead end? Had he simply moved on to other things?

I discovered that Steven Woods was Qiang’s Ph.D. student. Woods himself co-authored a paper on “Program plan matching: experiments with a constraint-based approach” in 2000, but then disappeared off the face of DBLP shortly thereafter. On to Wikipedia: In 1998 Steven co-founded a company, and went on to a distinguished career as an entrepreneur and industry executive, According to LInkedin he is now Senior Engineering Director and Site Lead for Google, and Google’s Tech Lead responsible for representing Google in Canada.

So it appears that industry’s gain was constraint programming and sofware engineering’s loss. The work has continued to be cited. Semantic Scholar provides a citation to the above book from as recently as recently as 2017:

YAZILIM YENİDEN YAPILAMAYA YÖNELİK BİR KURUMSAL MİMARI: MODEL GÜDÜMLÜ VE ONTOLOJİ TABANLI BİR YAKLAŞIM

which Google Translate tells me is Turkish for:

A CORPORATE ARCHITECTURE FOR SOFTWARE RECONSTRUCTION: A MODEL-DRIVEN AND ONTOLOGY-BASED APPROACH

But if there is someone out there with an interest in applying constraint satisfaction to program understanding, I suspect there is fertile ground yet to explore here. And perhaps you could get support from Google, especially if you live in Canada. 🙂