mboeh

$ history 1 | awk {'print $2, $3, $4'} | sort | uniq -c | sort -k1 -rn | head -n 30
    172 fg  
    164 git st 
    163 ls  
     72 ruby create_event_local.rb blah
     62 git push 
     59 git pull 
     54 git commit -m
     50 git di 
     47 bundle  

mboeh

# Summary: In MRI 1.9, if you keep threads in an array in a local variable, the threads may outlive the local variable.
# I have not yet been able to produce a scenario in which the threads are ever garbage-collected.
# You have to remove the thread from the array before it goes out of scope, e.g. using #pop or #clear.
# INPUT DESIRED: If anyone can demonstrate a condition in which a local array keeps threads and those threads are eventually GC'd.
# INPUT DESIRED: Is this expected behavior or a bug?
# NOTE: This test will not work as expected in JRuby, because its garbage collection works differently. Whether the same behavior exists in JRuby is an exercise for someone smarter than I am.

class Foo

  THREAD_PROC = lambda{ (0..10).to_a.map do Foo.new end }

mboeh

# http://blog.jazzychad.net/2012/08/01/array-iteration-problem.html

def add1(arr, val, n)
  range = (0 ... arr.length)
  indexes = n < 0 ? range.reverse_each : range.each
  n = n.zero? ? arr.length : n.abs
  
  indexes.each do |idx|
    if arr[idx] == val
      arr[idx] += 1

mboeh

class Object
  private :dup
  private :clone
  private :freeze
end

module ValueObject
  def self.included(into)
    into.send :public, :dup
    into.send :public, :clone

mboeh

This shows how different approaches to memoization work (or don't) in different Ruby engines.

Synopsis

If you're using the idiomatic Ruby approach to memoization, like this:

def data
  @memo ||= expensive_action
end

mboeh

#!/bin/sh
# backdroppify - sizes an image to the minimum size which will fill your entire screen & trims overflow
bgsize=`xwininfo -root | grep -- -geometry | cut -d' ' -f4 | cut -d+ -f1`
convert $1 -resize $bgsize^ -gravity center -extent $bgsize ~/.backdrop.jpg
set-backdrop

mboeh

require 'test/unit/testcase'
require 'test/unit' if $0 == __FILE__

class Proc
  
  def as_proc
    if arity == -1
      self 
    else
      aty = arity.abs - (arity < 0 ? 1 : 0)

mboeh

require 'celluloid'
require 'zip/zipfilesystem'
require 'uri'
require 'net/http'

class ZipManifest
  include Celluloid

  def initialize(filename)
    @urls = {}

mboeh

class Orz
  attr_reader :v
  def []=(v)
    @v = v
  end
end

orz = Orz.new
orz[] = :a
orz.v # ==> :a

mboeh

# NOTE: I just slapped this together as a proof of concept. Thread safety etc. is left to the reader.

module RTDocumentation

  def self.included(into)
    # method_added doesn't seem to work if mixed in
    into.send(:define_method, :method_added) do |name|
      if @_rtdoc_nextdoc
        @_rtdocs ||= {}
        @_rtdocs[name.to_s] = @_rtdoc_nextdoc