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clojure-spec
vlaaad 2022-08-23T20:29:26.655769Z
Does something like that make sense?
(defmulti dispatch identity)
(defmethod dispatch :default [v]
(:spec v))
(s/valid?
(s/multi-spec dispatch :spec)
{:spec (s/keys :req-un [::a ::b]) :a 1 :b 2})
=> true:default branch would be more complex, but the idea is that I have a complex rule to infer spec from the value, and I don't want to encode it in a single predicate that executes the rule and calls s/valid? inside because it will lose the error reporting/explanation. I.e. I don't want to do this:
(s/valid?
(s/spec #(s/valid? (:spec %) %))
{:spec (s/keys :req-un [::a ::b]) :a 1})
=> false(s/explain-data ...) will just say that (s/valid? (:spec %) %) is false and not that the :b is missingvlaaad 2022-08-23T20:31:36.840939Z
Explanation comparison:
(s/explain
(s/spec #(s/valid? (:spec %) %))
{:spec (s/keys :req-un [::a ::b]) :a 1})
=> {:spec ... :a 1} - failed: (valid? (:spec %) %)
(s/explain
(s/multi-spec dispatch :spec)
{:spec (s/keys :req-un [::a ::b]) :a 1})
=> {:spec ... :a 1} - failed: (contains? % :b)vlaaad 2022-08-25T08:37:27.852479Z
Any opinions?
vlaaad 2022-08-24T18:52:07.019989Z
check this out:
(defmacro def-dynamic-spec [name & fn-tail]
(let [multi-name (symbol (str name "-multi-fn"))]
`(do
(defmulti ~multi-name (constantly nil))
(defmethod ~multi-name nil ~@fn-tail)
(def ~name (s/multi-spec ~multi-name nil)))))