keymastervn

This list is based on aliases_spec.rb.

You can see also Module: RSpec::Matchers API.

matcher	aliased to	description
a_truthy_value	be_truthy	a truthy value
a_falsey_value	be_falsey	a falsey value
be_falsy	be_falsey	be falsy
a_falsy_value	be_falsey	a falsy value

keymastervn

require 'bundler/inline'

gemfile true do
  source 'https://rubygems.org'
  gem 'redis'
  gem 'hiredis'
  gem 'benchmark-ips'
end

require 'benchmark'

keymastervn

#!/bin/ruby --verion => 2.0.0-p353

Self

In Ruby, self is a special variable that always references the current object.

• Inside class or module definition, self refer to the Class or Module object.
• Inside instance method, self refer to future instance object.
• Inside class method, self refer to the class.i

keymastervn

# This file extends the Kernel's require function and adds the 
# AutoReload module which allows to reload files once they have changed
# on the disk.
#
# Basically, you just require your files as usual, and if you want to update
# the files, either call AutoReload.reload(file) or AutoReload.reload_all.
#
# Usage:
#   irb -rautoload
#

keymastervn

require 'memory_profiler'
require 'benchmark/ips'

puts "Memory stats for requiring mini_mime"
result = MemoryProfiler.report do
  require 'mini_mime'
end
puts "Total allocated: #{result.total_allocated_memsize} bytes (#{result.total_allocated} objects)"

puts "Memory stats for requiring marcel"

keymastervn

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

---

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

---

keymastervn

ruby '2.7.1'

gem 'rails', github: 'rails/rails'
gem 'tzinfo-data', '>= 1.2016.7'  # Don't rely on OSX/Linux timezone data

# Action Text
gem 'actiontext', github: 'basecamp/actiontext', ref: 'okra'
gem 'okra', github: 'basecamp/okra'

# Drivers

keymastervn

function mapValues(obj, fn) {
  return Object.keys(obj).reduce((result, key) => {
    result[key] = fn(obj[key], key);
    return result;
  }, {});
}

function pick(obj, fn) {
  return Object.keys(obj).reduce((result, key) => {
    if (fn(obj[key])) {

keymastervn

System Design Cheatsheet

Picking the right architecture = Picking the right battles + Managing trade-offs

Basic Steps

1. Clarify and agree on the scope of the system

• User cases (description of sequences of events that, taken together, lead to a system doing something useful)
  • Who is going to use it?
  • How are they going to use it?