gistfile1.txt

(defn block-categoly
     ;FIXME, stupid implementation.
     ;available options:
     ; :vacant :enterable :combustible
     ;usage:
     ; (block-categoly :vacant :enterable) => #{} of vacant and enterable
     ; (block-categoly :enterable :vacant) => #{} of vacant and enterable
     ;
     [&keys]
     (let [c (set keys)
           data
           [[Material/AIR #{:vacant :enterable}]
            [Material/WATER #{:vacant :enterable}] ;flowing
            [Material/LAVA #{:vacant :enterable}] ;flowing
            [Material/FIRE #{:vacant :enterable}]

            [Material/STATIONARY_WATER #{:enterable}] ; not vacant, we can have it.
            [Material/STATIONARY_LAVA  #{:enterable}] ; may be we need "obtainable" instead of "vacant" or unobtainable.

            [Material/WEB #{:combustible :enterable}]
            [Material/BROWN_MUSHROOM  #{:combustible :enterable}]
            [Material/RED_MUSHROOM #{:combustible :enterable}]
            [Material/RED_ROSE #{:combustible :enterable}]
            [Material/YELLOW_FLOWER #{:combustible :enterable}]
            [Material/WHEAT #{:combustible :enterable}]
            [Material/PUMPKIN_STEM #{:combustible :enterable}]
            [Material/MELON_STEM #{:combustible :enterable}]
            [Material/VINE #{:combustible :enterable}]
            [Material/GRASS #{:combustible :enterable}]
            [Material/DEAD_BUSH #{:combustible :enterable}]
            [Material/SUGAR_CANE #{:combustible :enterable}]

            [Material/LEAVES  #{:combustible}]
            [Material/MELON_BLOCK #{:combustible}]
            [Material/PUMPKIN #{:combustible}]
            [Material/WATER_LILY  #{}]
            [Material/CACTUS #{}]]
           ]
       (set (take-nth 2
                      (filter (fn [pair]
                                  (clojure.set/subset? (last pair) keys)) data)))))