[tannhaeuser]

The point of Prolog as a practical logic programming language really is that it is portable accross Prolog implementations based on ISO Prolog (and maybe prolog-commons API compatibility). If you're using a Prologish tool (a Java framework, say) that is not quite Prolog, then you're loosing the compatibility for very little gain IMHO.

Applications domains I've used Prolog for: discrete planning, game logic, limited/rule-based NLP such as postal address checking, combinatorial test case generation, decision problems in formal language theory used for eg. deciding properties of business processes, other small problems in software engineering such as code generation from domain models with roundtripping, or O/R mapping.

[vanderZwan]

> The point of Prolog as a practical logic programming language really is that it is portable accross Prolog implementations based on ISO Prolog (and maybe prolog-commons API compatibility). If you're using a Prologish tool (a Java framework, say) that is not quite Prolog, then you're loosing the compatibility for very little gain IMHO.

I feel like I might be missing something obvious, but I'm not getting what the "compatibility" you refer to would give me in my specific situations? It looks like you're saying "if you write a Prolog program, it's compatible across Prolog platforms." Well, sure, but how is that fundamentally more portable situation than (for example) "if I have a logic programming framework in ES16, it works in all browsers that run modern JavaScript"?

If I'm specifically trying to do something in the browser (again, for example) and have a problem within that context where logic programming might be useful, having a way to use logic programming in JS makes more sense, doesn't it?

[tannhaeuser]

I'm not disagreeing that if you're developing a Web app, embedding logical or constraint programming techniques into a JavaScript API could make sense. OTOH, there's an obvious way for data exchange between JavaScript and Prolog, in that JSON can be be parsed by using Prolog's embedded `op/2` predicate and operator-precedence parser for defining custom DSLs.

[jononor]

What would be the workflow in Prolog if I want to import a set of facts from an external source, like a database/JSON/CSV?

[tannhaeuser]

JSON could be parsed as a term by Prolog, with suitable priority/associativity definitions for the comma, colon, and curly brace operators.

For CSV, you could write a DCG grammar for the particular file format at hand.

Integration with a relational DB, itself being based on logic, would be very different. Most Prologs have APIs to map tables to predicates.

[e12e]

If you replace Prolog with SQL - does it make more sense?

[vanderZwan]

Yes, and I missed it because I was thinking in terms of "hmm, I wonder if there are any points in my client-side code-base that could be cleaned up by using logic programming?"