> In contrast, the imperative style of Esterel is confined to the domain of real-time embedded control systems. As a matter of fact, imperative reactivity is now often associated to the observer pattern, typical in object-oriented systems, because it heavily relies on side effects [20, 25]. However, short-lived callbacks (i.e., the observers) eliminate any vestige of structured programming, such as support for long-lasting loops and automatic variables [3], which are elementary capabilities of imperative languages. In this sense, callbacks actually disrupt imperative reactivity, becoming "our generation’s goto" [13, 15].
> We believe that the full range of reactive applications can benefit from the imperative style of Esterel, which we now refer to as Structured Reactive Programming (SRP). SRP extends the classical hierarchical control constructs of Structured Programming (SP) (i.e., concatenation, selection, and repetition [14]) to support continuous interaction with the environment.
It's so refreshing to read something like that after we've been hit over the head with "pure-FP is the only right way to program" for some time.
The way I see it, I think there are two approaches to solving problems. The first tries to see what tools we have available, tries to figure out what we can build, and then hopes the result is useful. The second looks at what we actually need, and sees if we can use anything at our disposal to get us closer to our goal. In many respects, PFP is the result of the first approach. We know how to verify PFP, right? Well, at least within the confines of first-order logic. So let's hope that's useful enough. Not that this kind of research isn't important, but I see it as searching under the (academic) lamppost, rather than research directed at providing the industry with what it actually needs.
I agree somewhat but maybe you are being a bit harsh on the PFP crowd: it was only 10 years ago where FP research was considered quite niche! Now the tables are reversed in that object people are now rebels and FP people are now the establishment, crazy. I think we are all searching for what are right answers, just that we are looking under different lampposts.
While Roberto's team in Brazil is more pragmatic, FP people like SPJ also care about producing useful artifacts. I would be worried if all PL research was oriented around FP, but it isn't :)
