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require 'yaml'
require 'optparse'
require 'set'

$options = { keys: [] }
$executable_name = 'envize.rb'

OptionParser.new do |opts|
  opts.banner = "Usage: #{$executable_name} [options]"

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Three Useful Ruby Methods you Didn't Know Existed, and What to do With Them Now You've Wised Up

Yep, it's time for some cool Ruby trickery.

String#force_encoding

At their core, Ruby strings are just sequences of bytes. How you or your computer chooses interpret and display those bytes can mean the difference between legible text and complete garbage. Consider UTF-8 text for example. We now have great Unicode support in Ruby (as of 1.9) via the String#encode method and its friends, but again, strings are really just bytes.

Telling Ruby your string is encoded in UTF-8 tells it how to print your string on the screen or in your web app. For example, let's say you have a string that contains Japanese text (says 'arigato') "ありがと". Furthermore, let's pretend Ruby thinks the string is encoded in ASCII, which doesn't support Japanese characters. If you tried to print your string in the terminal, you might see something like this: "\xE3\x81\x82\xE3\x82\x8A\xE3\x81\x8C\xE3\x81\xA8". What you're seeing

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require 'find'

def provide(*requires, &block)
  modules = requires.map do |req|
    Module.new do
      file_fragment = "#{req}.rb"

      file = Find.find(*($: + ['.'])) do |f|
        break f if f =~ /#{file_fragment}\z/
      end

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Introduction

You may have heard before that Ruby isn't a concurrent language. In other words, it's not capable of doing two things at once. For the most part, you're right - the canonical version of Ruby that we use at Lumos (called MRI) locks the interpreter to a single thread of execution. This means you can never truly run a task "in the background" within the same process. MRI relaxes the lock however for certain IO operations, including file operations and network activity. The Ruby interpreter will "unlock" itself whenever it detects an IO operation, meaning other threads get to run. Pretty cool :)

Since Ruby does support at least some level of concurrency, it would be cool if we could use it in our apps. There are a couple of great Ruby concurrency libraries out there - namely Celluloid and concurrent-ruby. I'm going to talk about concurrent-ruby in this gist because it's the one I know best.

P

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require 'json'
require 'cgi'

def convert(data)
  params = JSON.parse(data.gsub('=>', ':'))
  [].tap do |out|
    walk_hash(params, out, [])
  end.join('&')
end

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One of the language features that really impressed me when I first started using Ruby was all the magic of Enumerable. No other language I know of lets you iterate so effectively over collections of objects. Let's say you wanted to sum together an array of integers in Java, for example:

int[] numbers = new int[5] { 5, 3, 8, 1, 2 };
int sum = 0;

for (int i = 0; i < numbers.length; i ++) {
  sum += numbers[i];
}

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require 'twitter_cldr'

class NumberTransliterator
  class << self

    def to_english_str(str)
      str.each_char.map do |char|
        transliterate_char(char) || char
      end.join
    end

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module Grape
  class Endpoint
    def build_middleware_with_error_tracking
      builder = build_middleware_without_error_tracking
      builder.use(::ErrorTrackingMiddleware)

      # HAAAAACK!
      builder.instance_variable_get(:'@use').tap do |use_arr|
        middleware_proc = use_arr.delete_at(use_arr.size - 1)
        use_arr.insert(0, middleware_proc)

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12:12:11,975 ERROR [stderr] (ServerService Thread Pool -- 47) 2014-09-22T12:12:11.967-07:00: BeanManagerImpl: mbean already registered: org.jruby:type=Runtime,name=0,service=JITCompiler
12:12:11,975 ERROR [stderr] (ServerService Thread Pool -- 47) 2014-09-22T12:12:11.975-07:00: BeanManagerImpl: mbean already registered: org.jruby:type=Runtime,name=0,service=Config
12:12:11,976 ERROR [stderr] (ServerService Thread Pool -- 47) 2014-09-22T12:12:11.976-07:00: BeanManagerImpl: mbean already registered: org.jruby:type=Runtime,name=0,service=ParserStats
12:12:11,976 ERROR [stderr] (ServerService Thread Pool -- 47) 2014-09-22T12:12:11.976-07:00: BeanManagerImpl: mbean already registered: org.jruby:type=Runtime,name=0,service=ClassCache
12:12:11,976 ERROR [stderr] (ServerService Thread Pool -- 47) 2014-09-22T12:12:11.976-07:00: BeanManagerImpl: mbean already registered: org.jruby:type=Runtime,name=0,service=Runtime
12:12:13,237 ERROR [org.torquebox.core.runtime] (ServerService Thread Pool -- 47) Error during execution

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require 'twitter_cldr'

num = 1234.localize(:en)  # locale is optional, defaults to :en

# "one thousand two hundred thirty-four"
num.spellout

# ["SpelloutRules", "OrdinalRules"]
num.rbnf.group_names