9mm/lib/space-is-neighbor.fnl

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(local {: contains} (require :lib.contains))
(local {: head} (require :lib.head))
(local {: tail} (require :lib.tail))
(lambda space-is-neighbor? [all-neighbors from to]
;; i have learned to check that i'm passing the correct type of move
;; i.e. a number and not a string
(assert (= "number" (type from)) "from must be a number")
(assert (= "number" (type to)) "to must be a number")
(assert (= "table" (type all-neighbors)) "all-neighbors must be a table")
(let [neighborhood-list (icollect [_ n (ipairs all-neighbors)] (if (= from (head n)) n))
neighborhood (head neighborhood-list)
neighbors (tail neighborhood)
is-neighbor (contains neighbors to)]
is-neighbor))
{: space-is-neighbor?}