This sounds super interesting - I’d love to hear how you get on with this.

Sure, no problem :)….

At the moment one of the things I’ve been looking at is how board games et al are taught/instructed? You have some high level concepts like attack or move and then special vs general rules for them as well as how specifically they’re combined together… I’ve also sorta got attacking/defending working how I want at the moment, just trying to work out how it works with other bits…

is this clj or cljs?

Something like this:

(deftest combat-tests
  (testing "a functioning shield component blocks some attack event damage"
    (is (= (foo {:topics #{:attack} :damage 8}
                {:name :basic-shield
                 :description "A simple shield"
                 :topics #{:attack :block}
                 :block {:fn [- 3]}})
           {:topics #{:attack} :damage 5}))
    (is (= (foo {:topics #{:attack} :damage 8}
                {:name :broken-shield
                 :description "A broken shield"
                 :topics #{:attack :block}})
           {:topics #{:attack} :damage 8})))

  (testing "a functioning aura of invulnerability component blocks all attack event damage"
    (is (= (foo {:topics #{:attack} :damage 8}
                {:name :aegis-aura
                 :description "A aura of invulnerability"
                 :topics #{:attack :block :aura}
                 :block {:fn [:min 0]}})
           {:topics #{:attack} :damage 0}))
    (is (= (foo {:topics #{:attack} :damage 8}
                {:name :disrupted-aegis-aura
                 :description "A disrupted aura of invulnerability"
                 :topics #{:attack :block :aura}})
           {:topics #{:attack} :damage 8}))
    (is (= (foo {:topics #{:attack} :damage 8}
                {:name :perfect-aegis-aura
                 :description "An aura of invulnerability that invalidates the attack"
                 :topics #{:attack :block :aura}
                 :block {:warp (fn [_] nil)}})
           nil)))

  (testing "a functioning elemental resistance component blocks some elemental attack event damage"
    (is (= (foo {:topics #{:attack :fire} :damage 8}
                {:name :elemental-fire-resistance
                 :description "Fire elemental resistance"
                 :topics #{:attack :block}
                 :block {:when #(contains? (:topics %) :fire) :fn [- 3]}})
           {:topics #{:attack :fire} :damage 5}))
    (is (= (foo {:topics #{:attack :fire} :damage 8}
                {:name :elemental-ice-resistance
                 :description "Ice elemental resistance"
                 :topics #{:attack :block}
                 :block {:when #(contains? (:topics %) :ice) :fn [- 3]}})
           {:topics #{:attack :fire} :damage 8}))))

@U79NZHC6A Not sure that doing it this way is a good idea, but it’s the best concept I’ve come up with so far… Once these bits all work then I’ll just have to work out how to hang them off entities so that things like entities colliding trigger attack actions etc…

So if this works, I can create new items and functionality with a very small core of primitives =)… Hopefully it’ll also be beginner friendly. One annoyance however is that I can’t introspect the function as it’s already resolved, so telling what fn it is isn’t great, hopefully it won’t be a problem in practice…