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; Copyright (c) Laurent Petit and others, March 2009. All rights reserved.
; The use and distribution terms for this software are covered by the
; Eclipse Public License 1.0 (http://opensource.org/licenses/eclipse-1.0.php)
; which can be found in the file epl-v10.html at the root of this
; distribution.
; By using this software in any fashion, you are agreeing to be bound by
; the terms of this license.
; You must not remove this notice, or any other, from this software.
;; functions/macros variants of the ones that can be found in clojure.core
;; note to other contrib members: feel free to add to this lib
(ns clojure.contrib.core
(:use clojure.contrib.def))
(defmacro- defnilsafe [docstring non-safe-name nil-safe-name]
`(defmacro ~nil-safe-name ~docstring
{:arglists '([~'x ~'form] [~'x ~'form ~'& ~'forms])}
([x# form#]
`(let [~'i# ~x#] (when-not (nil? ~'i#) (~'~non-safe-name ~'i# ~form#))))
([x# form# & more#]
`(~'~nil-safe-name (~'~nil-safe-name ~x# ~form#) ~@more#))))
(defnilsafe
"Same as clojure.core/-> but returns nil as soon as the threaded value is nil itself (thus short-circuiting any pending computation).
Examples :
(-?> \"foo\" .toUpperCase (.substring 1)) returns \"OO\"
(-?> nil .toUpperCase (.substring 1)) returns nil
"
-> -?>)
(defnilsafe
"Same as clojure.core/.. but returns nil as soon as the threaded value is nil itself (thus short-circuiting any pending computation).
Examples :
(.?. \"foo\" .toUpperCase (.substring 1)) returns \"OO\"
(.?. nil .toUpperCase (.substring 1)) returns nil
"
.. .?.)
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