KamilLelonek

class ClientsController < ApplicationController
  def create
    @client = Client.new(params[:client])
    if @client.save
      redirect_to @client
    else
      flash.now[:error] = "Could not save client"
      render action: "new"
    end
  end

KamilLelonek

require_relative 'default_file_writer'
require_relative 'no_overwrite_file_writer'
require_relative 'no_null_file_writer'

file_writer = NoOverwriteFileWriter.new(
  NoNullFileWriter.new(
    DefaultFileWriter.new
  )
)

KamilLelonek

class NoNullFileWriter
  def initialize(default_file_writer)
    @default_file_writer = default_file_writer
  end

  def write(path, contents)
    fail_if_empty_contents(contents)
    default_file_writer.write(path, contents)
  end

KamilLelonek

class NoOverwriteFileWriter
  def initialize(default_file_writer)
    @default_file_writer = default_file_writer
  end

  def write(path, contents)
    fail_if_file_exist(path)
    default_file_writer.write(path, contents)
  end

KamilLelonek

class DefaultFileWriter
  def write(path, contents)
    IO.write(path, contents)
  end
end

KamilLelonek

class DefensiveFileWriter
  def write(path, contents)
    fail_if_empty_contents(contents)
    fail_if_file_exist(path)
    write_file(path, contents)
  end

  private
  def fail_if_empty_contents(contents)
    raise 'Nothing to write!' if empty_contents?(contents)

KamilLelonek

buildscript {
    repositories {
        maven { url 'https://dl.bintray.com/drummer-aidan/maven' }
        mavenCentral()
    }

    dependencies {
        classpath "com.android.tools.build:gradle:1.3.1"
        classpath "jp.leafytree.gradle:gradle-android-scala-plugin:1.4"
    }

KamilLelonek

defmodule Type do
  defmacro __using__(opts) do
    quote location: :keep, bind_quoted: [
      type:   Macro.escape(opts[:type],   unquote: true),
      values: Macro.escape(opts[:values], unquote: true),
    ] do
      @behaviour Ecto.Type

      def type,   do: type
      def values, do: values

KamilLelonek

 defmodule Yatzy.Score do
  def  upper(n, ds),           do: n * count(n, ds)
  defp count(n, ls),           do: select_elements(n, ls) |> Enum.count
  defp select_elements(n, ls), do: ls |> Enum.filter &(&1 == n)

  def chance(ds), do: ds |> Enum.reduce &(&1 + &2)

  def yatzy(ds) do
    case count_unique_elements(ds) do
      1 -> 50

KamilLelonek

Contract Num, Func[Num => Any], Proc => Any
def eight_divide_by(number, success_action, failure_action)
  case number
    # ...
    when 4 then success_action[2]
    when 2 then success_action[4]
    when 1 then success_action[8]
    when 0 then failure_action.call
  end
end