Ev Dolzhenko dolzenko

What is sync.Pool in golang and How to use it

sync.Pool (1/2)

Many Go libraries include custom thread-safe free lists, like this:

var objPool = make(chan *Object, 10)

func obj() *Object {

select {

RSpec Helper Example

Here's an example of a rspec test helper that will let you sign in as a given user.

Create spec/support/helpers/authentication.rb with the following:

module Helpers
  module Authentication
    def sign_in_as(user)

Originally published in June 2008

When hiring Ruby on Rails programmers, knowing the right questions to ask during an interview was a real challenge for me at first. In 30 minutes or less, it's difficult to get a solid read on a candidate's skill set without looking at code they've previously written. And in the corporate/enterprise world, I often don't have access to their previous work.

To ensure we hired competent ruby developers at my last job, I created a list of 15 ruby questions -- a ruby measuring stick if you will -- to select the cream of the crop that walked through our doors.

What to expect

Candidates will typically give you a range of responses based on their experience and personality. So it's up to you to decide the correctness of their answer.

	module Net
	class HTTP
	alias_method '__initialize__', 'initialize'

	def initialize(*args,&block)
	__initialize__(*args, &block)
	ensure
	@debug_output = $stderr ### if ENV['HTTP_DEBUG']
	end
	end

	['mysql2', 'sequel', 'pp'].each(&method(:require))
	DB = Sequel.connect('mysql2://root@localhost/tmp')
	DB.tables.each {\|t\| DB.drop_table(t) }

	def t(name, columns, *rows)
	DB.create_table(name) do
	columns.each.with_index do \|column, ind\|
	type = rows[0][ind].class.to_s
	send type, column
	end

	require 'benchmark'
	module IRB
	def self.before_eval
	end
	def self.after_eval
	end
	def self.around_eval(&block)
	@timing = Benchmark.measure do
	block.call
	end

	#! /usr/bin/env ruby

	require 'bundler'

	paths = Bundler.load.specs.map(&:full_gem_path)

	system("ack '#{ARGV[0]}' #{paths.join(' ')}")

	;; OSX - Update the PATH to match that from the shell
	(defun set-exec-path-from-shell-PATH ()
	(let ((path-from-shell
	(replace-regexp-in-string "[[:space:]\n]*$" ""
	(shell-command-to-string "$SHELL -l -c 'echo $PATH'"))))
	(setenv "PATH" path-from-shell)
	(setq exec-path (split-string path-from-shell path-separator))))
	(when (equal system-type 'darwin) (set-exec-path-from-shell-PATH))

	;; Go mode

	require 'stamp'
	require 'text-table'

	def how(ts)
	hour = (ts.to_f / 3600).floor
	hour % 24 + ((hour / 24 + 4).floor % 7) * 24
	end

	from = Time.utc(2013, 4, 7)
	to = Time.utc(2013, 4, 7 + 7)