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      definline

      clojure.core

      Available since 1.0 (source)
      • (definline name & decl)
      Experimental - like defmacro, except defines a named function whose
body is the expansion, calls to which may be expanded inline as if
it were a macro. Cannot be used with variadic (&) args.
      © Rich Hickey. All rights reserved. Eclipse Public License 1.0
      0 Examples
      No examples for clojure.core/definline.
      See Also
      clojure.core/defmacro

      Like defn, but the resulting function name is declared as a macro and will be used as a macro by t...

      Added by KingMob
      2 Notes
        By , created 12.4 years ago

        Note that, as for macros, the arguments to definline are potentially subject to double evaluation if they are used more than once in the body. For example:

        user=> (definline bad-sqr [x] `(* ~x ~x))
#'user/bad-sqr
user=> (bad-sqr (do (println "x") 5))
x
x
25
        By , created 11.4 years ago

        Any non-like-a-function behaviour should be avoided, because otherwise function will behave differently depending on whether it's inlined or not:

        user=> (definline bad-if [cond then] `(if ~cond ~then))
#'user/bad-if
user=> (bad-if nil (do (prn :side-effect) :not-returned))
nil
user=> (let [bad-if bad-if] (bad-if nil (do (prn :side-effect)     :not-returned)))
:side-effect
nil