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I have issue in splitting seqs on a flow: ; RAW (def raw-order-flow (m/seed '([1 2 3] [4 5]))) (m/? (m/reduce conj raw-order-flow)) ; helper fn (defn split-seq-flow [s] (m/ap (loop [s s] (m/amb (first s) (let [s (rest s)] (when (seq s) (recur s))))))) (def order-flow (m/ap (let [data (m/?> raw-order-flow)] (m/?> (split-seq-flow data))))) (m/? (m/reduce conj order-flow)) ;; => [1 2 3 nil 4 5 nil] There should no be any nil There. I want the Output to be [1 2 3 4 5]. Whatever I do with amb .. either I get nothing back or it add the last recursion which produces nil.
with m/eduction and a transducer
(m/? (m/reduce conj (m/eduction cat (m/seed [[1 2 3] [4 5]]))))trying to code eduction cat behavior
(defn concat* [coll-flow]
(m/ap
(when-let [coll (m/?> coll-flow)]
(loop [coll coll]
(if (seq coll)
(m/amb (first coll) (recur (rest coll)))
(m/amb))))))
;; works with empty seq & nil values
(m/? (m/reduce conj
(concat* (m/seed [[1 2] [] [4] [nil] [5]]))))
;; res: [1 2 4 nil 5]@U0569GLFZ thanks! Your concat* fn also loop-recurs. So the way how it us written must be another answer. I tried something like that.. but either got no outgoing data pushed. Or I would get a compile exception saying in ap recur needs to be the last form.
If you do not recur, then „(when …)“ returns nil. And you get (amb (first s) nil). but what you need is a (amb) without any arguments if rest is nil. (amb) won’t produce any value. You need something like this: (if (seq s) (amb ( first s) (recur (rest s))) (amb)) Sorry for bad formatting, I am on mobile