With "constraint programming" languages, do you mean languages such as MiniZinc that provide dedicated syntax for some tasks? I am asking because support for c

With "constraint programming" languages, do you mean languages such as MiniZinc that provide dedicated syntax for some tasks? I am asking because support for constraint programming is among the most important and most distinguishing features of common Prolog systems: All widely used Prolog systems (GNU-Prolog, SICStus etc.) ship at least with a constraint solver over integers, and often with many more, such as constraints over Herbrand terms (dif/2), constraints over rational numbers and also constraints over Boolean variables (SAT constraints). So, support for constraint programming is typically provided also natively by Prolog systems, with a simple and also very expressive syntax that blends in seamlessly into Prolog like any other relation. There was a recent HN discussion about why Prolog is not yet more popular: https://news.ycombinator.com/item?id=14439137 https://news.ycombinator.com/item?id=14439137 In my view, Prolog implementations are now becoming interesting because they are now quite robust, feature-rich and also reasonably efficient.