Question

How should this python be expressed

gl_enums = ... # map from name to values for opengl enums
# use with gl_enums["enum name"]

in clojure? This works, but is it right?

(def gl-enums ...) ; map from name to values for opengl enums
(defn gl-enum [k] (or (gl-enums k) (throw (SomeException.))))
; use with (gl-enum :enum-name)

edit: for clarification, this question is about the exception-throwing part, not the map-defining part

Answer 1

Your original example is OK. Two approaches you are also likely to come across:

;; not very idiomatic
(defn example
  [m]
  (if (contains? m :name)
    (:name m)
    (throw (IllegalArgumentException. (format "key %s is missing" :name)))))

;; idiomatic
(defn example
  [m]
  (if-let [v (:name m)]
    v
    (throw (IllegalArgumentException. (format "key %s is missing" :name)))))

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