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(use 'clojure.java.io) 
(let [pred (every-pred
             #(.isDirectory %)
             #(not (.startsWith (.getName %) "."))
             #(not (some (partial = (.getName %)) ["Exclude Name 0" "Exclude Name 1" "Exclude Name 2"])))
        dest "/Path/to/Destination"
        src "/Path/to/Source" ]
    (doseq [f (filter pred (-> src file .listFiles seq))]
      (.renameTo f (file dest (.getName f))) ))

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(define (memoize f)
  (define ht (make-hash))
  (define (f-mem . args)
    (if (hash-has-key? ht args)
        (hash-ref ht args)
        (begin
          (hash-set! ht args (apply f args))
          (hash-ref ht args))))
  f-mem)

kisai

#!/bin/bash
export JAVA_OPTS="-Xmx2048m -XX:ReservedCodeCacheSize=256m -XX:MaxPermSize=256m -Djava.net.preferIPv4Stack=true -XX:NewRatio=3 -XX:+UseConcMarkSweepGC -XX:+UseParNewGC -XX:+CMSClassUnloadingEnabled -Dfile.encoding=UTF-8 -XX:+TieredCompilation -XX:TieredStopAtLevel=1"
export JRUBY_OPTS="--1.9 -J-noverify -J-XX:+TieredCompilation -J-XX:TieredStopAtLevel=1"
torquebox run -b 0.0.0.0

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Class Dog
   has_many :tags
   belongs_to :person
end

Class Person
  has_many :dogs
end

d = Dog.new

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#Sample 1
puts "#{$@.first}: #{$!.message} (#{$!.class})", $@.drop(1).map{|s| "\t#{s}"}

#Sample 2
puts "#{e.backtrace.first}: #{e.message} (#{e.class})", e.backtrace.drop(1).map{|s| "\t#{s}"}

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true || true and false #=> false
true || true  && false #=> true

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ary = ["A", "B", "C", "B", "A"]

ary.group_by { |e| e }.select { |k, v| v.size > 1 }.map(&:first)

ary.sort.chunk { |e| e }.select { |e, count| count.size > 1 }.map(&:first)

ary.select { |e| ary.count(e) > 1 }.uniq

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rails g migration add_public_and_private_to_document public:string private:string

bin/rails generate migration AddSomeRefAndSomeColumnToSomeTable some:references some_column:boolean

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obj = SomeObject.new

obj.define_singleton_method(:new_method) do
  "do some things"
end

# Using a mixin

module AdditionalMethods
  def new_method

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class Class
  #firstly, the * decoration on the parameter variable
  #indicates that the parameters should come in as an array
  #of whatever was sent
  def my_attr_accessor(*args)

    #We simply iterate through each passed in argument...
    args.each do |arg|
      
      #Here's the getter