| Hello Peter, Fred, Brian, and all, As several of you know, we’re on the hunt for a static-only variant of occam-Pi, which I’ve tentatively named occam-Sigma (Greek s for static) - sorry, Fred! So I am studying Fred’s dissertation. Relating mobile data (section 4.2) and undefined usage checking (4.6), I notice that the undefined usage algorithm assumes a mobile communication is one-way, while the pointer exchange supports a swap. Could there be a mobile primitive that would swap data both sides of which are defined, e.g. “?!” as CHAN MOBILE INT c: PAR MOBILE INT x: SEQ ... define x c ?! x ... continue work with x being in classic occam CHAN OF INT c1, c2: PAR INT x: SEQ ... define x INT y: SEQ y := x PAR c1 ! y c2 ? x ... continue work with x and the same for the second component of the PAR (channels swapped in the classic occam)? This would correspond to the “swap caddy” that I drew on the board at CPA2016, while what is described in Fred’s dissertation would be a “slider slot”. Larry Dickson |