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clojureplumatic-schema

Can one make a predicate function from a Plumatic Schema?

I want to make a predicate function that when something matches schema X returns true, else false.

Solution

  • You can use schema/check which works like schema/validate but returns errors directly as a value instead of throwing exception or nil when no errors are found:

    (schema/defschema string-vector
  [schema/Str])

(defn str-vec? [arg]
  (nil? (schema/check string-vector arg)))

(str-vec? ["hi"])   ; => true
(str-vec? ["hi" 5]) ; => false

    There is also schema/checker which "compiles an efficient checker for schema":

    (let [str-vec?-checker (schema/checker string-vector)]
  (defn str-vec? [arg]
    (nil? (str-vec?-checker arg))))