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specter 2023-07-11
Hi! is traverse lazy?
for example:
(reduce (fn [acc x] (foo acc x))
init-val
(sp/traverse [sp/ALL (sp/pred some-pred) (sp/view bar)] coll))bar be executed on all the collection anyway?
Or should foo return a reduced value on some element, will traverse halt and subsequent elements will not meet (sp/view bar)?
Hi I have a list of maps, I want to return one of the maps based on the value of the :name key in the maps. i.e. give me the name where :name = "fred"?
(select-any [ALL (pred #(= (:name %) "fred"))] list-of-maps)That does not seem to work. I am getting the "%" is not allowed.
#(= (:name %) "fred")It was what I hoped for
forgot the # for the lambda 🫠
Thanks that worked.
nathanmarz 2023-07-11T16:26:21.010539Z
@lidorcg it's not "lazy" in the sense of clojure's lazy data structures, but it doesn't execute anything unless the caller requests the next element
nathanmarz 2023-07-11T16:26:55.056409Z
so if your reduce function stops iteration using reduced, traverse won't look at additional elements
nathanmarz 2023-07-11T16:27:23.648249Z
so if your reduce function was doing that, bar would not necessarily be called on all elements
Thanks 🙏🏼