Mercurial > lasercutter

     1 ;   Copyright (c) Laurent Petit and others, March 2009. All rights reserved.

     2 

     3 ;   The use and distribution terms for this software are covered by the

     4 ;   Eclipse Public License 1.0 (http://opensource.org/licenses/eclipse-1.0.php)

     5 ;   which can be found in the file epl-v10.html at the root of this 

     6 ;   distribution.

     7 ;   By using this software in any fashion, you are agreeing to be bound by

     8 ;   the terms of this license.

     9 ;   You must not remove this notice, or any other, from this software.

    10 

    11 ;; functions/macros variants of the ones that can be found in clojure.core

    12 

    13 ;; note to other contrib members: feel free to add to this lib

    14 

    15 (ns

    16   ^{:author "Laurent Petit (and others)"

    17      :doc "Functions/macros variants of the ones that can be found in clojure.core 

    18  (note to other contrib members: feel free to add to this lib)"}

    19   clojure.contrib.core

    20   (:use clojure.contrib.def))

    21 

    22 (defmacro- defnilsafe [docstring non-safe-name nil-safe-name]

    23   `(defmacro ~nil-safe-name ~docstring

    24      {:arglists '([~'x ~'form] [~'x ~'form ~'& ~'forms])}

    25 	   ([x# form#]

    26 	     `(let [~'i# ~x#] (when-not (nil? ~'i#) (~'~non-safe-name ~'i# ~form#))))

    27   	 ([x# form# & more#]

    28 	     `(~'~nil-safe-name (~'~nil-safe-name ~x# ~form#) ~@more#))))

    29        

    30 (defnilsafe 

    31   "Same as clojure.core/-> but returns nil as soon as the threaded value is nil itself (thus short-circuiting any pending computation).

    32    Examples :

    33    (-?> \"foo\" .toUpperCase (.substring 1)) returns \"OO\"

    34    (-?> nil .toUpperCase (.substring 1)) returns nil

    35    "

    36    -> -?>)

    37     

    38 (defnilsafe 

    39   "Same as clojure.core/.. but returns nil as soon as the threaded value is nil itself (thus short-circuiting any pending computation).

    40    Examples :

    41    (.?. \"foo\" .toUpperCase (.substring 1)) returns \"OO\"

    42    (.?. nil .toUpperCase (.substring 1)) returns nil

    43    "

    44    .. .?.)

    45 

    46 (defnilsafe

    47   "Same as clojure.core/->> but returns nil as soon as the threaded value is nil itself (thus short-circuiting any pending computation).

    48    Examples :

    49    (-?>> (range 5) (map inc)) returns (1 2 3 4 5)

    50    (-?>> [] seq (map inc)) returns nil

    51    "

    52   ->> -?>>)

    53 

    54 ;; ----------------------------------------------------------------------

    55 ;; scgilardi at gmail

    56 

    57 (defn dissoc-in

    58   "Dissociates an entry from a nested associative structure returning a new

    59   nested structure. keys is a sequence of keys. Any empty maps that result

    60   will not be present in the new structure."

    61   [m [k & ks :as keys]]

    62   (if ks

    63     (if-let [nextmap (get m k)]

    64       (let [newmap (dissoc-in nextmap ks)]

    65         (if (seq newmap)

    66           (assoc m k newmap)

    67           (dissoc m k)))

    68       m)

    69     (dissoc m k)))

    70 

    71 (defn new-by-name

    72   "Constructs a Java object whose class is specified by a String."

    73   [class-name & args]

    74   (clojure.lang.Reflector/invokeConstructor

    75    (clojure.lang.RT/classForName class-name)

    76    (into-array Object args)))

    77 

    78 (defn seqable?

    79   "Returns true if (seq x) will succeed, false otherwise."

    80   [x]

    81   (or (seq? x)

    82       (instance? clojure.lang.Seqable x)

    83       (nil? x)

    84       (instance? Iterable x)

    85       (-> x .getClass .isArray)

    86       (string? x)

    87       (instance? java.util.Map x)))

    88 

    89 ;; ----------------------------------------------------------------------
author	Robert McIntyre <rlm@mit.edu>
date	Sat, 21 Aug 2010 06:25:44 -0400
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