Mercurial > repos > other > SevenLanguagesInSevenWeeks
comparison 3-Prolog/day1-self-study.pl @ 55:3a20e8b49bc4
Write some self-study code with an additional stretch rule to find collaborations
| author | IBBoard <dev@ibboard.co.uk> |
|---|---|
| date | Tue, 26 Sep 2017 20:26:45 +0100 |
| parents | |
| children | 2bbb377ddeb0 |
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| 54:91d02b3d74f8 | 55:3a20e8b49bc4 |
|---|---|
| 1 % Make a KB of books and authors and query it. | |
| 2 book(the_long_earth). | |
| 3 book(night_watch). | |
| 4 book(lord_of_the_rings). | |
| 5 book(route_666). | |
| 6 book(krokodil_tears). | |
| 7 author(terry_pratchett). | |
| 8 author(stephen_baxter). | |
| 9 author(jrr_tolkein). | |
| 10 author(jack_yeovil). | |
| 11 wrote(terry_pratchett, the_long_earth). | |
| 12 wrote(stephen_baxter, the_long_earth). | |
| 13 wrote(terry_pratchett, night_watch). | |
| 14 wrote(jrr_tolkein, lord_of_the_rings). | |
| 15 wrote(jack_yeovil, route_666). | |
| 16 wrote(jack_yeovil, krokodil_tears). | |
| 17 | |
| 18 collaborated(Author1, Author2) :- \+(Author1 = Author2), author(Author1), author(Author2), | |
| 19 wrote(Author1, Book), wrote(Author2, Book), book(Book). | |
| 20 % collaborated(terry_pratchett, stephen_baxter). returns true, but collaborated(Author1, Author2). just says "no", as does | |
| 21 % collaborated(terry_pratchett, OtherAuthor). - for some reason it isn't filling in answers. | |
| 22 % | |
| 23 % If I remove "\+(Author1 = Author2)" then it successfully returns stephen_baxter for terry_pratchett but also returns | |
| 24 % Pratchett himself as a valid answer as well. | |
| 25 % | |
| 26 % wrote(terry_pratchett, Book). works to return all books by an author, though. |