A sample from their user manual[0]:
% print even numbers between 1 and 10
main :- count(1).
count(11).
count(N) :- N =< 10 | even(N), N2 is N + 1, count(N2).
even(N) :- M is N \\ 2, even(M, N).
even(0, N) :- writeln(N).
even(_, _) :- otherwise | true.
From the same author, and in the same family of languages, is FLENG: http://www.call-with-current-continuation.org/fleng/fleng.ht...
It lacks Strand's distributed features but includes prolog's unification.
I wasn't involved, but I remember considerable interest in Strand from parallel programming people in the lab about the time it appeared. I don't think that lasted long, but unfortunately I don't remember why it failed (if I knew then).
SISAL was probably a better bet as a dataflow-ish language, but I don't remember anyone else looking at it, despite Manchester being "just" down the road.
No idea if related in any meaningful way, but https://github.com/rust-lang/chalk/tree/master/chalk-engine/... (a "PROLOG-like logic solver" for the Rust trait system) also makes use of "strands"
I find this fascinating, if a bit incomprehensible, but what might an intended use case be?
A good introduction to concurrent logic languages:
Parlog86 and the dining logicians G. A. Ringwood Communications of the ACM January 1988 https://doi.org/10.1145/35043.35044
From the User's Manual:
三個和尚沒水å–
(Chinese Proverb)
Their implementation approach is interesting: they have their own custom Forth implementation, with a kernel written in assembly language (ARM, aarch64, x86_64 and ppc64le). Then Strand is written in a mixture of Forth and itself.