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dexterous/fns-should-be-1-form.clj

Created May 6, 2025 20:34
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  1. dexterous created this gist May 6, 2025.
    38 changes: 38 additions & 0 deletions fns-should-be-1-form.clj
    View file
    Original file line number Diff line number Diff line change
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    ;; From https://github.com/ring-clojure/ring/blob/a915a44/ring-core/src/ring/middleware/session/cookie.clj#L29
    (defn- hmac
    "Generates a Base64 HMAC with the supplied key on a string of data."
    [key data]
    (let [mac (Mac/getInstance hmac-algorithm)]
    (.init mac (SecretKeySpec. key hmac-algorithm))
    (codec/base64-encode (.doFinal mac data))))

    ;; I would prefer to write it like this.
    (defn- hmac
    "Generates a Base64 HMAC with the supplied key on a string of data."
    [key data]
    (codec/base64-encode
    (-> (doto (Mac/getInstance hmac-algorithm)
    (.init (SecretKeySpec. key hmac-algorithm)))
    (.doFinal data))))

    ;; Expands as follows
    (pprint (clojure.walk/macroexpand-all
    '(defn- hmac
    "Generates a Base64 HMAC with the supplied key on a string of data."
    [key data]
    (codec/base64-encode
    (-> (doto (Mac/getInstance hmac-algorithm)
    (.init (SecretKeySpec. key hmac-algorithm)))
    (.doFinal data))))))

    (def hmac
    (fn*
    ([key data]
    (codec/base64-encode
    (.
    (let*
    [G__136 (Mac/getInstance hmac-algorithm)]
    (. G__136 init (new SecretKeySpec key hmac-algorithm))
    G__136)
    doFinal
    data)))))