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@nberger
Created July 8, 2015 03:22
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recipes with core.logic
(ns recipes.core
(:refer-clojure :exclude [==])
(:use [clojure.core.logic]
[clojure.core.logic.pldb :as pldb]))
(db-rel in-larder i)
(db-rel recipe r)
(db-rel in-recipe r i)
(db-rel compound-ingredient i is)
(declare ingredient-in-lardero)
(defne any-ingredient-in-lardero [ingredients]
([[?i . ?morei]] (conda [(ingredient-in-lardero ?i)]
[(emptyo ?morei) fail]
[(any-ingredient-in-lardero ?morei)])))
(defne all-ingredients-in-lardero [ingredients]
([[?i . ?morei]]
(ingredient-in-lardero ?i)
(conda [(emptyo ?morei)]
[(all-ingredients-in-lardero ?morei)])))
(defn ingredient-in-lardero [i]
(conde
[(fresh [composition op sub-ingredients]
(compound-ingredient i composition)
(conso op sub-ingredients composition)
(conde
[(== :or op) (any-ingredient-in-lardero sub-ingredients)]
[(== :and op) (all-ingredients-in-lardero sub-ingredients)]))]
[(in-larder i)]))
(defn possible-recipe [r]
(recipe r)
(fresh [ingredients]
(in-recipe r ingredients)
(all-ingredients-in-lardero ingredients)))
(def recipes (db
[compound-ingredient :carrots-or-peas [:or :carrots :peas]]
[compound-ingredient :onions-or-garlic [:or :onions :garlic]]
[compound-ingredient :carrots-and-onions [:and :carrots :onions]]
[compound-ingredient :rice-and-peas [:and :rice :peas]]
[compound-ingredient :carrots-onions-or-rice-peas [:or :carrots-and-onions :rice-and-peas]]
[recipe :risotto-a]
[recipe :risotto-b]
[in-recipe :risotto-a [:carrots-or-peas :rice :onions-or-garlic]]
[in-recipe :risotto-b [:garlic :carrots-onions-or-rice-peas]]))
(def larder-1 (db [in-larder :carrots]
[in-larder :rice]
[in-larder :garlic]))
(def larder-2 (db [in-larder :rice]
[in-larder :peas]
[in-larder :garlic]))
(with-dbs [recipes larder-1]
(run* [q]
(possible-recipe q)))
;=> (:risotto-a)
(with-dbs [recipes larder-2]
(run* [q]
(possible-recipe q)))
;=> (:risotto-a :risotto-b)
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