michalmarczyk

(comment
  (:b (DefaultMap. :foo {:a 1}))
  ; => :foo
  (:a (DefaultMap. :foo {:a 1}))
  ; => 1
  (merge-with conj (DefaultMap. [] {}) {:a 1} {:a 2} {:a 3})
  ; => {:a [1 2 3]}
  )

;;; method implementations basically taken from clojure.core/emit-defrecord

michalmarczyk

;(use '[clojure.tools.macro :only [symbol-macrolet]])

(defmacro letrec
  "Like let, but the bindings may be mutually recursive, provided that
   the heads of all values can be evaluated independently.

   This means that functions, lazy sequences, delays and the like can
   refer to other bindings regardless of the order in which they
   appear in the letrec form."
  [bindings & body]

michalmarczyk

;;; Written when pondering
;;; http://stackoverflow.com/questions/9086926/create-a-proxy-for-an-specific-instance-of-an-object-in-clojure

(defmacro delegating-proxy [o class-and-ifaces ctor-args & impls]
  (let [oname (gensym)]
    (letfn [(delegating-impls [^java.lang.reflect.Method ms]
              (let [mname (symbol (.getName ^java.lang.reflect.Method (first ms)))
                    arity-groups (partition-by #(count (.getParameterTypes ^java.lang.reflect.Method %)) ms)
                    max-arity (max-key #(count (.getParameterTypes ^java.lang.reflect.Method %)) ms)]
                `(~mname

michalmarczyk

(alembic/distill '[org.clojure/data.avl "0.0.17"])
(alembic/distill '[net.cgrand/xforms "0.12.1"])

(require '[clojure.data.avl :as avl]
         '[net.cgrand.xforms :as x])


(defn join [keyfn xforms-map]
  (comp
    (x/multiplex xforms-map)

michalmarczyk

;; Written to answer https://stackoverflow.com/questions/47254742/sort-primitive-array-with-custom-comparator-on-clojure
;; See https://gist.github.com/michalmarczyk/11bbfd0b19b6357f533b192bf9da84ac for the single-threaded version

(defn order3 [xs]
  (let [rnd (java.util.Random.)
        a1 (double-array xs)
        a2 (long-array (alength a1))]
    (dotimes [i (alength a2)]
      (aset a2 i i))
    (letfn [(quicksort [^long l ^long h]

michalmarczyk

;; Written to answer https://stackoverflow.com/questions/47254742/sort-primitive-array-with-custom-comparator-on-clojure

(defn order2 [xs]
  (let [rnd (java.util.Random.)
        a1 (double-array xs)
        a2 (long-array (alength a1))]
    (dotimes [i (alength a2)]
      (aset a2 i i))
    (letfn [(quicksort [^long l ^long h]
              (if (< l h)

michalmarczyk

;;; See the inspirational SO question: http://stackoverflow.com/questions/3346382

(require 'clojure.contrib.trace)

(defn trace-ns
  "Replaces each function from the given namespace with a version wrapped
  in a tracing call. Can be undone with untrace-ns. ns should be a namespace
  object or a symbol."
  [ns]
  (doseq [s (keys (ns-interns ns))

michalmarczyk

;;; See the comment threads here:
;;; http://stackoverflow.com/questions/41677617/are-all-variables-in-clojure-constant

(loop [x 1
       f (fn [] x)]
  (if (== 1 x)
    (recur 0 f)
    (f)))
;= 1

michalmarczyk

;;; all code in this function lifted from the clojure-mode function
;;; from clojure-mode.el
(defun clojure-font-lock-setup ()
  (interactive)
  (set (make-local-variable 'lisp-indent-function)
       'clojure-indent-function)
  (set (make-local-variable 'lisp-doc-string-elt-property)
       'clojure-doc-string-elt)
  (set (make-local-variable 'font-lock-multiline) t)

michalmarczyk

;; for now, consumer starts producer
;; -- must make sure that output chan already on comm-chan before producer starts

(defn producer [comm-chan]
  (go (loop []
        (if-let [c (<! comm-chan)]
          (do
            (>! c (rand))
            (>! comm-chan c)
            (recur))