dudo

module FastJsonapi
  module ErrorSerializer
    extend ActiveSupport::Concern

    included do
      include FastJsonapi::ObjectSerializer

      attr_accessor :with_root_key

      set_id :title

dudo

# Return a boolean indicating whether the number is a palindrome. Raises a
# TypeError if the argument is not an integer
#
# Caveat: Try to accomplish this without converting the number to a string.
#   The goal is to understand your approach to a problem with constraints
#   rather than seeing how quickly you can jump to an easy solution.
#
# Example
#   palindrome?(1001) => true
#   palindrome?(1234) => false

dudo

class String
  def balanced?
    pairs = { '{' => '}', '[' => ']', '(' => ')' }

    brackets = chars.each_with_object([]) do |char, stack|
      if bracket = pairs[char]
        stack << bracket
      elsif pairs.values.include?(char)
        next if stack.pop == char

dudo

class String
  def encrypt(k)
    lower_alphabet = [*'a'..'z']
    lower_translation_map = lower_alphabet.zip(lower_alphabet.rotate(k%26)).to_h
    upper_alphabet = [*'A'..'Z']
    upper_translation_map = upper_alphabet.zip(upper_alphabet.rotate(k%26)).to_h
    translation_map = lower_translation_map.merge(upper_translation_map)

    chars.map { |char| translation_map[char] || char }.join
  end

dudo

class Order < ActiveRecord::Base
  scope :paid, -> { where(id: Payment.paid.select(:order_id)) }
end

# SELECT "orders".* FROM "orders" WHERE "orders"."id" IN (
#   SELECT "payments"."order_id"
#   FROM "payments"
#   WHERE "payments"."state" IN ('charged', 'authorized')
# )

dudo

package main

import (
	"code.google.com/p/go-tour/tree"
	"fmt"
)

// Walk walks the tree t sending all values
// from the tree to the channel ch.
func Walk(t *tree.Tree, ch chan int) {

dudo

class ApplicationRecord < ActiveRecord::Base
  self.abstract_class = true

  def self.human_enum_name(enum_name, enum_value)
    I18n.t("activerecord.attributes.#{model_name.i18n_key}.#{enum_name.to_s.pluralize}.#{enum_value}")
  end

  def self.human_enum_collection(enum_name)
    send(enum_name.to_s.pluralize).keys.map do |val|
      [human_enum_name(enum_name, val), val]

dudo

require 'csv'
require 'activerecord-import'

module ActsAsCsv
  extend ActiveSupport::Concern

  class_methods do
    def filename
      if const_defined? :CSV_FILENAME
        self::CSV_FILENAME

dudo

The 4 simple math functions

Lerp

Lerp is the acronym for linear interpolation. The idea is very simple, you have 2 values, and you want to “walk” between those values by a factor.

func lerp = (start, end, factor) => 
  start * (1-factor) + end * factor;

dudo

RSpec.describe Api::ClientBase do
  subject(:api) { described_class.new(config) }

  let(:scheme) { 'https' }
  let(:host) { Faker::Internet.domain_name }
  let(:port) { 3000 }

  let(:config) do
    {
      'scheme' => scheme,