[ { "path": "das-0010-fast-tests-with-and-without-rails/test", "content": "#!/bin/bash\n#\n# From Destroy All Software screencast #10, at:\n# http://destroyallsoftware.com/screencasts/catalog/fast-tests-with-and-without-rails\n#\n# Released under the MIT license: http://opensource.org/licenses/MIT\n#\n# Put this in the script/ directory of your Rails app, then run it with a spec\n# filename. If the spec uses spec_helper, it'll be run inside Bundler.\n# Otherwise, it'll be run directly with whatever `rspec` executable is on the\n# path.\n\nset -e\n\nneed_rails=1\n\nif [ $# -gt 0 ]; then # we have args\n filename=$1\n # Remove trailing line numbers from filename, e.g. spec/my_spec.rb:33\n grep_filename=`echo $1 | sed 's/:.*$//g'`\n\n # if we can't match \"spec_helper\" in our file we have a stand-alone spec\n grep -r '\\bspec_helper\\b' $grep_filename > /dev/null || need_rails=''\nelse # we have no args\n filename='spec'\nfi\n\ncommand='rspec'\n\nif [ $need_rails ]; then\n command=\"ruby -S bundle exec $command\"\nfi\n\nRAILS_ENV=test $command $filename\n\n" }, { "path": "das-0026-controller-refactoring-demo-part-2/account_controller.rb", "content": "#-- copyright\n# ChiliProject is a project management system.\n#\n# Copyright (C) 2010-2011 the ChiliProject Team\n#\n# This program is free software; you can redistribute it and/or\n# modify it under the terms of the GNU General Public License\n# as published by the Free Software Foundation; either version 2\n# of the License, or (at your option) any later version.\n#\n# See doc/COPYRIGHT.rdoc for more details.\n#++\n\nclass AccountController < ApplicationController\n include CustomFieldsHelper\n\n # prevents login action to be filtered by check_if_login_required application scope filter\n skip_before_filter :check_if_login_required\n\n # Login request and validation\n def login\n if request.get?\n logout_user\n else\n authenticate_user\n end\n end\n\n # Log out current user and redirect to welcome page\n def logout\n logout_user\n redirect_to home_url\n end\n\n # Enable user to choose a new password\n def lost_password\n redirect_to(home_url) && return unless Setting.lost_password?\n if params[:token]\n handle_existing_token\n else\n generate_token\n end\n end\n\n def handle_existing_token\n @token = Token.find_by_action_and_value(\"recovery\", params[:token])\n redirect_to(home_url) && return unless have_valid_token?\n @user = @token.user\n if request.post?\n reset_password\n else\n render :template => \"account/password_recovery\"\n end\n end\n\n def have_valid_token?\n @token and !@token.expired?\n end\n\n def reset_password\n @user.password = params[:new_password]\n @user.password_confirmation = params[:new_password_confirmation]\n if @user.save\n @token.destroy\n flash[:notice] = l(:notice_account_password_updated)\n redirect_to :action => 'login'\n else\n render :template => \"account/password_recovery\"\n end\n end\n\n def generate_token\n return unless request.post?\n\n user = User.find_by_mail(params[:mail])\n\n if ensure_user_exists(user) && ensure_no_external_auth(user)\n create_new_token(user)\n end\n end\n\n def ensure_user_exists(user)\n if user\n true\n else\n flash.now[:error] = l(:notice_account_unknown_email)\n false\n end\n end\n\n def ensure_no_external_auth(user)\n if user.auth_source_id\n flash.now[:error] = l(:notice_can_t_change_password)\n false\n else\n true\n end\n end\n\n def create_new_token(user)\n token = Token.new(:user => user, :action => \"recovery\")\n if token.save\n Mailer.deliver_lost_password(token)\n flash[:notice] = l(:notice_account_lost_email_sent)\n redirect_to :action => 'login', :back_url => home_url\n return\n end\n end\n\n # User self-registration\n def register\n redirect_to(home_url) && return unless Setting.self_registration? || session[:auth_source_registration]\n if request.get?\n session[:auth_source_registration] = nil\n @user = User.new(:language => Setting.default_language)\n else\n @user = User.new(params[:user])\n @user.admin = false\n @user.register\n if session[:auth_source_registration]\n @user.activate\n @user.login = session[:auth_source_registration][:login]\n @user.auth_source_id = session[:auth_source_registration][:auth_source_id]\n if @user.save\n session[:auth_source_registration] = nil\n self.logged_user = @user\n flash[:notice] = l(:notice_account_activated)\n redirect_to :controller => 'my', :action => 'account'\n end\n else\n @user.login = params[:user][:login]\n @user.password, @user.password_confirmation = params[:password], params[:password_confirmation]\n\n case Setting.self_registration\n when '1'\n register_by_email_activation(@user)\n when '3'\n register_automatically(@user)\n else\n register_manually_by_administrator(@user)\n end\n end\n end\n end\n\n # Token based account activation\n def activate\n redirect_to(home_url) && return unless Setting.self_registration? && params[:token]\n token = Token.find_by_action_and_value('register', params[:token])\n redirect_to(home_url) && return unless token and !token.expired?\n user = token.user\n redirect_to(home_url) && return unless user.registered?\n user.activate\n if user.save\n token.destroy\n flash[:notice] = l(:notice_account_activated)\n end\n redirect_to :action => 'login'\n end\n\n private\n\n def logout_user\n if User.current.logged?\n cookies.delete Redmine::Configuration['autologin_cookie_name']\n Token.delete_all([\"user_id = ? AND action = ?\", User.current.id, 'autologin'])\n self.logged_user = nil\n end\n end\n\n def authenticate_user\n if Setting.openid? && using_open_id?\n open_id_authenticate(params[:openid_url])\n else\n password_authentication\n end\n end\n\n def password_authentication\n user = User.try_to_login(params[:username], params[:password])\n\n if user.nil?\n invalid_credentials\n elsif user.new_record?\n onthefly_creation_failed(user, {:login => user.login, :auth_source_id => user.auth_source_id })\n else\n # Valid user\n successful_authentication(user)\n end\n end\n\n\n def open_id_authenticate(openid_url)\n authenticate_with_open_id(openid_url, :required => [:nickname, :fullname, :email], :return_to => signin_url) do |result, identity_url, registration|\n if result.successful?\n user = User.find_or_initialize_by_identity_url(identity_url)\n if user.new_record?\n # Self-registration off\n redirect_to(home_url) && return unless Setting.self_registration?\n\n # Create on the fly\n user.login = registration['nickname'] unless registration['nickname'].nil?\n user.mail = registration['email'] unless registration['email'].nil?\n user.firstname, user.lastname = registration['fullname'].split(' ') unless registration['fullname'].nil?\n user.random_password\n user.register\n\n case Setting.self_registration\n when '1'\n register_by_email_activation(user) do\n onthefly_creation_failed(user)\n end\n when '3'\n register_automatically(user) do\n onthefly_creation_failed(user)\n end\n else\n register_manually_by_administrator(user) do\n onthefly_creation_failed(user)\n end\n end\n else\n # Existing record\n if user.active?\n successful_authentication(user)\n else\n account_pending\n end\n end\n end\n end\n end\n\n def successful_authentication(user)\n # Valid user\n self.logged_user = user\n # generate a key and set cookie if autologin\n if params[:autologin] && Setting.autologin?\n set_autologin_cookie(user)\n end\n call_hook(:controller_account_success_authentication_after, {:user => user })\n redirect_back_or_default :controller => 'my', :action => 'page'\n end\n\n def set_autologin_cookie(user)\n token = Token.create(:user => user, :action => 'autologin')\n cookie_options = {\n :value => token.value,\n :expires => 1.year.from_now,\n :path => Redmine::Configuration['autologin_cookie_path'],\n :secure => Redmine::Configuration['autologin_cookie_secure'],\n :httponly => true\n }\n cookies[Redmine::Configuration['autologin_cookie_name']] = cookie_options\n end\n\n # Onthefly creation failed, display the registration form to fill/fix attributes\n def onthefly_creation_failed(user, auth_source_options = { })\n @user = user\n session[:auth_source_registration] = auth_source_options unless auth_source_options.empty?\n render :action => 'register'\n end\n\n def invalid_credentials\n logger.warn \"Failed login for '#{params[:username]}' from #{request.remote_ip} at #{Time.now.utc}\"\n flash.now[:error] = l(:notice_account_invalid_creditentials)\n end\n\n # Register a user for email activation.\n #\n # Pass a block for behavior when a user fails to save\n def register_by_email_activation(user, &block)\n token = Token.new(:user => user, :action => \"register\")\n if user.save and token.save\n Mailer.deliver_register(token)\n flash[:notice] = l(:notice_account_register_done)\n redirect_to :action => 'login'\n else\n yield if block_given?\n end\n end\n\n # Automatically register a user\n #\n # Pass a block for behavior when a user fails to save\n def register_automatically(user, &block)\n # Automatic activation\n user.activate\n user.last_login_on = Time.now\n if user.save\n self.logged_user = user\n flash[:notice] = l(:notice_account_activated)\n redirect_to :controller => 'my', :action => 'account'\n else\n yield if block_given?\n end\n end\n\n # Manual activation by the administrator\n #\n # Pass a block for behavior when a user fails to save\n def register_manually_by_administrator(user, &block)\n if user.save\n # Sends an email to the administrators\n Mailer.deliver_account_activation_request(user)\n account_pending\n else\n yield if block_given?\n end\n end\n\n def account_pending\n flash[:notice] = l(:notice_account_pending)\n redirect_to :action => 'login'\n end\nend\n" }, { "path": "das-0030-some-vim-tips/grb256.vim", "content": "\" Based on\nruntime colors/ir_black.vim\n\nlet g:colors_name = \"grb256\"\n\nhi pythonSpaceError ctermbg=red guibg=red\n\nhi Comment ctermfg=darkgray\n\nhi StatusLine ctermbg=darkgrey ctermfg=white\nhi StatusLineNC ctermbg=black ctermfg=lightgrey\nhi VertSplit ctermbg=black ctermfg=lightgrey\nhi LineNr ctermfg=darkgray\nhi CursorLine guifg=NONE guibg=#121212 gui=NONE ctermfg=NONE ctermbg=234\nhi Function guifg=#FFD2A7 guibg=NONE gui=NONE ctermfg=yellow ctermbg=NONE cterm=NONE\nhi Visual guifg=NONE guibg=#262D51 gui=NONE ctermfg=NONE ctermbg=236 cterm=NONE\n\nhi Error guifg=NONE guibg=NONE gui=undercurl ctermfg=16 ctermbg=red cterm=NONE guisp=#FF6C60 \" undercurl color\nhi ErrorMsg guifg=white guibg=#FF6C60 gui=BOLD ctermfg=16 ctermbg=red cterm=NONE\nhi WarningMsg guifg=white guibg=#FF6C60 gui=BOLD ctermfg=16 ctermbg=red cterm=NONE\nhi SpellBad guifg=white guibg=#FF6C60 gui=BOLD ctermfg=16 ctermbg=160 cterm=NONE\n\n\" ir_black doesn't highlight operators for some reason\nhi Operator guifg=#6699CC guibg=NONE gui=NONE ctermfg=lightblue ctermbg=NONE cterm=NONE\n\nhighlight DiffAdd term=reverse cterm=bold ctermbg=lightgreen ctermfg=16\nhighlight DiffChange term=reverse cterm=bold ctermbg=lightblue ctermfg=16\nhighlight DiffText term=reverse cterm=bold ctermbg=lightgray ctermfg=16\nhighlight DiffDelete term=reverse cterm=bold ctermbg=lightred ctermfg=16\n\nhighlight PmenuSel ctermfg=16 ctermbg=156\n\n" }, { "path": "das-0030-some-vim-tips/ir_black.vim", "content": "\" ir_black color scheme\n\" More at: http://blog.infinitered.com/entries/show/8\n\n\n\" ********************************************************************************\n\" Standard colors used in all ir_black themes:\n\" Note, x:x:x are RGB values\n\"\n\" normal: #f6f3e8\n\" \n\" string: #A8FF60 168:255:96 \n\" string inner (punc, code, etc): #00A0A0 0:160:160\n\" number: #FF73FD 255:115:253 \n\" comments: #7C7C7C 124:124:124\n\" keywords: #96CBFE 150:203:254 \n\" operators: white\n\" class: #FFFFB6 255:255:182\n\" method declaration name: #FFD2A7 255:210:167\n\" regular expression: #E9C062 233:192:98\n\" regexp alternate: #FF8000 255:128:0\n\" regexp alternate 2: #B18A3D 177:138:61\n\" variable: #C6C5FE 198:197:254\n\" \n\" Misc colors:\n\" red color (used for whatever): #FF6C60 255:108:96 \n\" light red: #FFB6B0 255:182:176\n\"\n\" brown: #E18964 good for special\n\"\n\" lightpurpleish: #FFCCFF\n\" \n\" Interface colors:\n\" background color: black\n\" cursor (where underscore is used): #FFA560 255:165:96\n\" cursor (where block is used): white\n\" visual selection: #1D1E2C \n\" current line: #151515 21:21:21\n\" search selection: #07281C 7:40:28\n\" line number: #3D3D3D 61:61:61\n\n\n\" ********************************************************************************\n\" The following are the preferred 16 colors for your terminal\n\" Colors Bright Colors\n\" Black #4E4E4E #7C7C7C\n\" Red #FF6C60 #FFB6B0\n\" Green #A8FF60 #CEFFAB\n\" Yellow #FFFFB6 #FFFFCB\n\" Blue #96CBFE #FFFFCB\n\" Magenta #FF73FD #FF9CFE\n\" Cyan #C6C5FE #DFDFFE\n\" White #EEEEEE #FFFFFF\n\n\n\" ********************************************************************************\nset background=dark\nhi clear\n\nif exists(\"syntax_on\")\n syntax reset\nendif\n\nlet colors_name = \"ir_black\"\n\n\n\"hi Example guifg=NONE guibg=NONE gui=NONE ctermfg=NONE ctermbg=NONE cterm=NONE\n\n\" General colors\nhi Normal guifg=#f6f3e8 guibg=black gui=NONE ctermfg=NONE ctermbg=NONE cterm=NONE\nhi NonText guifg=#070707 guibg=black gui=NONE ctermfg=black ctermbg=NONE cterm=NONE\n\nhi Cursor guifg=black guibg=white gui=NONE ctermfg=black ctermbg=white cterm=reverse\nhi LineNr guifg=#3D3D3D guibg=black gui=NONE ctermfg=darkgray ctermbg=NONE cterm=NONE\n\nhi VertSplit guifg=#202020 guibg=#202020 gui=NONE ctermfg=darkgray ctermbg=darkgray cterm=NONE\nhi StatusLine guifg=#CCCCCC guibg=#202020 gui=italic ctermfg=white ctermbg=darkgray cterm=NONE\nhi StatusLineNC guifg=black guibg=#202020 gui=NONE ctermfg=blue ctermbg=darkgray cterm=NONE \n\nhi Folded guifg=#a0a8b0 guibg=#384048 gui=NONE ctermfg=NONE ctermbg=NONE cterm=NONE\nhi Title guifg=#f6f3e8 guibg=NONE gui=bold ctermfg=NONE ctermbg=NONE cterm=NONE\nhi Visual guifg=NONE guibg=#262D51 gui=NONE ctermfg=NONE ctermbg=darkgray cterm=NONE\n\nhi SpecialKey guifg=#808080 guibg=#343434 gui=NONE ctermfg=NONE ctermbg=NONE cterm=NONE\n\nhi WildMenu guifg=green guibg=yellow gui=NONE ctermfg=black ctermbg=yellow cterm=NONE\nhi PmenuSbar guifg=black guibg=white gui=NONE ctermfg=black ctermbg=white cterm=NONE\n\"hi Ignore guifg=gray guibg=black gui=NONE ctermfg=NONE ctermbg=NONE cterm=NONE\n\nhi Error guifg=NONE guibg=NONE gui=undercurl ctermfg=white ctermbg=red cterm=NONE guisp=#FF6C60 \" undercurl color\nhi ErrorMsg guifg=white guibg=#FF6C60 gui=BOLD ctermfg=white ctermbg=red cterm=NONE\nhi WarningMsg guifg=white guibg=#FF6C60 gui=BOLD ctermfg=white ctermbg=red cterm=NONE\n\n\" Message displayed in lower left, such as --INSERT--\nhi ModeMsg guifg=black guibg=#C6C5FE gui=BOLD ctermfg=black ctermbg=cyan cterm=BOLD\n\nif version >= 700 \" Vim 7.x specific colors\n hi CursorLine guifg=NONE guibg=#121212 gui=NONE ctermfg=NONE ctermbg=NONE cterm=BOLD\n hi CursorColumn guifg=NONE guibg=#121212 gui=NONE ctermfg=NONE ctermbg=NONE cterm=BOLD\n hi MatchParen guifg=#f6f3e8 guibg=#857b6f gui=BOLD ctermfg=white ctermbg=darkgray cterm=NONE\n hi Pmenu guifg=#f6f3e8 guibg=#444444 gui=NONE ctermfg=NONE ctermbg=NONE cterm=NONE\n hi PmenuSel guifg=#000000 guibg=#cae682 gui=NONE ctermfg=NONE ctermbg=NONE cterm=NONE\n hi Search guifg=NONE guibg=NONE gui=underline ctermfg=NONE ctermbg=NONE cterm=underline\nendif\n\n\" Syntax highlighting\nhi Comment guifg=#7C7C7C guibg=NONE gui=NONE ctermfg=darkgray ctermbg=NONE cterm=NONE\nhi String guifg=#A8FF60 guibg=NONE gui=NONE ctermfg=green ctermbg=NONE cterm=NONE\nhi Number guifg=#FF73FD guibg=NONE gui=NONE ctermfg=magenta ctermbg=NONE cterm=NONE\n\nhi Keyword guifg=#96CBFE guibg=NONE gui=NONE ctermfg=blue ctermbg=NONE cterm=NONE\nhi PreProc guifg=#96CBFE guibg=NONE gui=NONE ctermfg=blue ctermbg=NONE cterm=NONE\nhi Conditional guifg=#6699CC guibg=NONE gui=NONE ctermfg=blue ctermbg=NONE cterm=NONE \" if else end\n\nhi Todo guifg=#8f8f8f guibg=NONE gui=NONE ctermfg=red ctermbg=NONE cterm=NONE\nhi Constant guifg=#99CC99 guibg=NONE gui=NONE ctermfg=cyan ctermbg=NONE cterm=NONE\n\nhi Identifier guifg=#C6C5FE guibg=NONE gui=NONE ctermfg=cyan ctermbg=NONE cterm=NONE\nhi Function guifg=#FFD2A7 guibg=NONE gui=NONE ctermfg=brown ctermbg=NONE cterm=NONE\nhi Type guifg=#FFFFB6 guibg=NONE gui=NONE ctermfg=yellow ctermbg=NONE cterm=NONE\nhi Statement guifg=#6699CC guibg=NONE gui=NONE ctermfg=lightblue ctermbg=NONE cterm=NONE\n\nhi Special guifg=#E18964 guibg=NONE gui=NONE ctermfg=white ctermbg=NONE cterm=NONE\nhi Delimiter guifg=#00A0A0 guibg=NONE gui=NONE ctermfg=cyan ctermbg=NONE cterm=NONE\nhi Operator guifg=white guibg=NONE gui=NONE ctermfg=white ctermbg=NONE cterm=NONE\n\nhi link Character Constant\nhi link Boolean Constant\nhi link Float Number\nhi link Repeat Statement\nhi link Label Statement\nhi link Exception Statement\nhi link Include PreProc\nhi link Define PreProc\nhi link Macro PreProc\nhi link PreCondit PreProc\nhi link StorageClass Type\nhi link Structure Type\nhi link Typedef Type\nhi link Tag Special\nhi link SpecialChar Special\nhi link SpecialComment Special\nhi link Debug Special\n\n\n\" Special for Ruby\nhi rubyRegexp guifg=#B18A3D guibg=NONE gui=NONE ctermfg=brown ctermbg=NONE cterm=NONE\nhi rubyRegexpDelimiter guifg=#FF8000 guibg=NONE gui=NONE ctermfg=brown ctermbg=NONE cterm=NONE\nhi rubyEscape guifg=white guibg=NONE gui=NONE ctermfg=cyan ctermbg=NONE cterm=NONE\nhi rubyInterpolationDelimiter guifg=#00A0A0 guibg=NONE gui=NONE ctermfg=blue ctermbg=NONE cterm=NONE\nhi rubyControl guifg=#6699CC guibg=NONE gui=NONE ctermfg=blue ctermbg=NONE cterm=NONE \"and break, etc\n\"hi rubyGlobalVariable guifg=#FFCCFF guibg=NONE gui=NONE ctermfg=lightblue ctermbg=NONE cterm=NONE \"yield\nhi rubyStringDelimiter guifg=#336633 guibg=NONE gui=NONE ctermfg=lightgreen ctermbg=NONE cterm=NONE\n\"rubyInclude\n\"rubySharpBang\n\"rubyAccess\n\"rubyPredefinedVariable\n\"rubyBoolean\n\"rubyClassVariable\n\"rubyBeginEnd\n\"rubyRepeatModifier\n\"hi link rubyArrayDelimiter Special \" [ , , ]\n\"rubyCurlyBlock { , , }\n\nhi link rubyClass Keyword \nhi link rubyModule Keyword \nhi link rubyKeyword Keyword \nhi link rubyOperator Operator\nhi link rubyIdentifier Identifier\nhi link rubyInstanceVariable Identifier\nhi link rubyGlobalVariable Identifier\nhi link rubyClassVariable Identifier\nhi link rubyConstant Type \n\n\n\" Special for Java\n\" hi link javaClassDecl Type\nhi link javaScopeDecl Identifier \nhi link javaCommentTitle javaDocSeeTag \nhi link javaDocTags javaDocSeeTag \nhi link javaDocParam javaDocSeeTag \nhi link javaDocSeeTagParam javaDocSeeTag \n\nhi javaDocSeeTag guifg=#CCCCCC guibg=NONE gui=NONE ctermfg=darkgray ctermbg=NONE cterm=NONE\nhi javaDocSeeTag guifg=#CCCCCC guibg=NONE gui=NONE ctermfg=darkgray ctermbg=NONE cterm=NONE\n\"hi javaClassDecl guifg=#CCFFCC guibg=NONE gui=NONE ctermfg=white ctermbg=NONE cterm=NONE\n\n\n\" Special for XML\nhi link xmlTag Keyword \nhi link xmlTagName Conditional \nhi link xmlEndTag Identifier \n\n\n\" Special for HTML\nhi link htmlTag Keyword \nhi link htmlTagName Conditional \nhi link htmlEndTag Identifier \n\n\n\" Special for Javascript\nhi link javaScriptNumber Number \n\n\n\" Special for Python\n\"hi link pythonEscape Keyword \n\n\n\" Special for CSharp\nhi link csXmlTag Keyword \n\n\n\" Special for PHP\n" }, { "path": "das-0070-time-to-first-request/time_to_first_request.sh", "content": "#!/bin/bash\n\nmain() {\n print_runtime > /dev/null\n print_runtime\n}\n\nprint_runtime() {\n pid=$(start_server)\n runtime=$(time_command wait_for_server)\n baseline=$(time_command wait_for_server)\n echo $runtime - $baseline | bc\n kill -9 $pid\n}\n\nstart_server() {\n cd example\n rackup >/dev/null 2>&1 &\n echo $!\n}\n\ntime_command() {\n local cmd=$*\n TIMEFORMAT=\"%3R\"\n (time $cmd) 2>&1\n}\n\nwait_for_server() {\n while true; do\n lsof -i :9292 > /dev/null\n if [[ $? == 0 ]]; then\n break\n fi\n done\n}\n\nmain\n\n" }, { "path": "das-0094-computing-by-constructing/everything.py", "content": "#!/usr/bin/env python3\n\nNULL = (\n lambda x: x\n)\n\nTRUE = (\n lambda t: lambda f: t(NULL)\n)\nFALSE = (\n lambda t: lambda f: f(NULL)\n)\nIF = (\n lambda cond: lambda t: lambda f: cond(t)(f)\n)\n\nZERO = (\n lambda f: lambda x: x\n)\n\nADD1 = (\n lambda n: lambda f: lambda x: f( n(f)(x) )\n)\nADD = (\n lambda n: lambda m: n(ADD1)(m)\n)\n\n# Is this number equal to zero?\nIS_ZERO = (\n lambda n: n(lambda x: FALSE)(TRUE)\n)\n\n# Subtract 1: opposite of S, so SUB1(ONE) == ZERO.\n# Like Y, this is more complex and subtle than most\n# of our functions have been. It's OK to skip over it\n# during this introduction.\nSUB1 = (\n (lambda n:\n lambda f:\n lambda x: n (lambda g: lambda h: h(g(f)))\n (lambda u: x)\n (lambda u: u))\n)\n\n# Multiplication: \"add m to zero n times\".\nMULT = (\n lambda n: lambda m: n(lambda x:\n ADD(x)(m))(ZERO)\n)\n\nONE = (\n ADD1(ZERO)\n)\nSIX = (\n ADD1(ADD1(ADD1(ADD1(ADD1(ADD1(ZERO))))))\n)\n" }, { "path": "das-0094-computing-by-constructing/lambda.py", "content": "#!/usr/bin/env python3\n\nONE = 1\nIS_ZERO = lambda x: x == 0\nSUB1 = lambda x: x - 1\nMULT = lambda x: lambda y: x * y\nIF = lambda cond: lambda t_func: lambda f_func: t_func(None) if cond else f_func(None)\n\nprint(\n (\n lambda myself: (\n lambda n: (\n IF(\n IS_ZERO(n)\n )(\n lambda _: ONE\n )(\n lambda _: MULT(n)( myself(myself)(SUB1(n)) )\n )\n )\n )\n )(\n lambda myself: (\n lambda n: (\n IF(\n IS_ZERO(n)\n )(\n lambda _: ONE\n )(\n lambda _: MULT(n)( myself(myself)(SUB1(n)) )\n )\n )\n )\n )\n (6)\n)\n" }, { "path": "das-0095-power-of-lambda-calculus/everything.py", "content": "#!/usr/bin/env python3\n\nNULL = (\n lambda x: x\n)\n\nTRUE = (\n lambda t: lambda f: t(NULL)\n)\nFALSE = (\n lambda t: lambda f: f(NULL)\n)\nIF = (\n lambda cond: lambda t: lambda f: cond(t)(f)\n)\n\nZERO = (\n lambda f: lambda x: x\n)\n\nADD1 = (\n lambda n: lambda f: lambda x: f( n(f)(x) )\n)\nADD = (\n lambda n: lambda m: n(ADD1)(m)\n)\n\n# Is this number equal to zero?\nIS_ZERO = (\n lambda n: n(lambda x: FALSE)(TRUE)\n)\n\n# Subtract 1: opposite of S, so SUB1(ONE) == ZERO.\n# Like Y, this is more complex and subtle than most\n# of our functions have been. It's OK to skip over it\n# during this introduction.\nSUB1 = (\n (lambda n:\n lambda f:\n lambda x: n (lambda g: lambda h: h(g(f)))\n (lambda u: x)\n (lambda u: u))\n)\n\n# Multiplication: \"add m to zero n times\".\nMULT = (\n lambda n: lambda m: n(lambda x:\n ADD(x)(m))(ZERO)\n)\n\nONE = (\n ADD1(ZERO)\n)\nSIX = (\n ADD1(ADD1(ADD1(ADD1(ADD1(ADD1(ZERO))))))\n)\n" }, { "path": "das-0095-power-of-lambda-calculus/lambda.py", "content": "#!/usr/bin/env python3\n\nprint(\n ( lambda myself: ( lambda n: ( ( lambda cond: lambda t: lambda f: cond(t)(f))( ( lambda n: n(lambda x: ( lambda t: lambda f: f(( lambda x: x))))(( lambda t: lambda f: t(( lambda x: x)))))(n))( lambda _:( ( lambda n: lambda f: lambda x: f( n(f)(x) ))(( lambda f: lambda x: x))) )( lambda _: ( lambda n: lambda m: n(lambda x: ( lambda n: lambda m: n(( lambda n: lambda f: lambda x: f( n(f)(x) )))(m))(x)(m))(( lambda f: lambda x: x)))(n)( myself(myself)(( (lambda n: lambda f: lambda x: n (lambda g: lambda h: h(g(f))) (lambda u: x) (lambda u: u)))(n)) )))))( lambda myself: ( lambda n: ( ( lambda cond: lambda t: lambda f: cond(t)(f))( ( lambda n: n(lambda x: ( lambda t: lambda f: f(( lambda x: x))))(( lambda t: lambda f: t(( lambda x: x)))))(n))( lambda _:( ( lambda n: lambda f: lambda x: f( n(f)(x) ))(( lambda f: lambda x: x))) )( lambda _: ( lambda n: lambda m: n(lambda x: ( lambda n: lambda m: n(( lambda n: lambda f: lambda x: f( n(f)(x) )))(m))(x)(m))(( lambda f: lambda x: x)))(n)( myself(myself)(( (lambda n: lambda f: lambda x: n (lambda g: lambda h: h(g(f))) (lambda u: x) (lambda u: u)))(n)) )))))\n\n (( ( lambda n: lambda f: lambda x: f( n(f)(x) ))(( lambda n: lambda f: lambda x: f( n(f)(x) ))(( lambda n: lambda f: lambda x: f( n(f)(x) ))(( lambda n: lambda f: lambda x: f( n(f)(x) ))(( lambda n: lambda f: lambda x: f( n(f)(x) ))(( lambda n: lambda f: lambda x: f( n(f)(x) ))(( lambda f: lambda x: x)))))))))\n\n (lambda x: x + 1)(0)\n)\n" }, { "path": "das-0102-data-compressor-from-scratch/LICENSE", "content": "Copyright 2017 Gary Bernhardt\n\nPermission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the \"Software\"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:\n\nThe above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.\n\nTHE SOFTWARE IS PROVIDED \"AS IS\", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.\n" }, { "path": "das-0102-data-compressor-from-scratch/README", "content": "These are the files used in Destroy All Software production 0102, \"Data\nCompressor From Scratch\", available at:\n\n https://www.destroyallsoftware.com/screencasts/catalog/data-compressor-from-scratch\n\nThe files are:\n\n- RUNME.sh, which wasn't used in the screencast, but exists to give you an\n easy way to run this code and see it work. You can execute it via\n `./RUNME.sh` (without the backquotes).\n\n- garyzip.rb, which is the file written in the screencast.\n\n- bin.rb, which defines BinPacker and BinUnpacker, responsible for packing\n sequences of int8s, int16s (unused in the screencast), int32s, and arbitrary\n bits into bytes.\n\n- rendertree.rb, which provides the `render_tree` function used to show the\n Huffman coding trees visually.\n\n- tree.dot, a manually-created tree diagram shown at the beginning of the\n screencast. You can render it via `dot -Tpng tree.dot | ./imgcat` (requires\n iTerm 2 or a terminal implementing iTerm 2's PNG rendering escape codes).\n\n- imgcat, which is distributed by the authors of iTerm 2 but included here for\n convenience. It allows us to print PNGs to the terminal. It will only work\n with iTerm 2 or other terminals that implement iTerm 2's PNG rendering\n escape codes.\n\nDEPENDENCIES\n\n- Ruby 2.4.1 (or probably older or newer versions, but try 2.4.1 if anything\n goes wrong).\n- For the tree rendering, iTerm 2 version 3.0.15.\n\nSUPPORT\n\nThis code is entirely unsupported and is for educational purposes only.\n\nLICENSE\n\nAll files here is released under the MIT license, with the exception of\n`imgcat`, whose copyright is held by the authors of iTerm 2. See the file\n`LICENSE`.\n" }, { "path": "das-0102-data-compressor-from-scratch/RUNME.sh", "content": "#!/usr/bin/env bash\n\nset -e -o pipefail\n\necho -n \"abbcccc\" | ./garyzip.rb compress | hexdump\n\n" }, { "path": "das-0102-data-compressor-from-scratch/bin.rb", "content": "# This file was used in Destroy All Software production 0102, \"Data Compressor\n# From Scratch\". It wasn't shown in the screencast, so it's not designed to be\n# as readable as the main code. All of this code is exactly as used in the\n# screencast except for the addition of comments.\n#\n# To see how this file was used to build a data compressor, visit:\n#\n# https://www.destroyallsoftware.com/screencasts/catalog/data-compressor-from-scratch\n\nclass BinPacker\n def initialize\n @bits = []\n end\n\n def int32(int)\n @bits << [int_to_bits(int, 32), int]\n self\n end\n\n def int16(int)\n @bits << [int_to_bits(int, 16), int]\n self\n end\n\n def int8(int)\n @bits << [int_to_bits(int, 8), int]\n self\n end\n\n def int(int, bit_count)\n @bits << [int_to_bits(int, bit_count), int]\n self\n end\n\n def bits(bits)\n @bits << [bits, bits]\n self\n end\n\n def pack\n [flattened_bits.map(&:to_s).join].pack(\"b*\")\n end\n\n def flattened_bits\n @bits.map { |bits, original| bits }.flatten(1)\n end\n\n # This function was banged out to be used once during recording, without\n # regard for whether anyone would ever read it. Oh well!\n def debug\n # Some ANSI escape codes that we'll use\n red = \"\\e[31;49m\"\n reset = \"\\e[0m\"\n\n # Pack up the original packed values into DebugValues containing DebugBits.\n # The DebugValues carry the original data plus the serialized bits; the\n # DebugBits carry the original bits plus the colorized bits.\n debug_values = @bits.each_with_index.map do |(bits, original), index|\n mark_this_group = index % 2 == 0\n debug_bits = bits.map do |bit|\n bit_string = mark_this_group ? red + bit.to_s + reset : bit.to_s\n DebugBit.new(bit_string, bit)\n end\n DebugValue.new(debug_bits, original)\n end\n\n # Print the original bit groups with their added alternating colors.\n $stderr.puts \"Original values (#{debug_values.length}):\"\n bit_strings = debug_values.map(&:debug_bits).map do |group|\n # Reverse so the bits are printed in decreasing significance order, as\n # expected by humans.\n group.map(&:colorized_bit).reverse.join\n end\n original_values = debug_values.map(&:original).map(&:to_s)\n max_original_length = original_values.map(&:length).max\n bit_strings.zip(original_values).each do |bit_string, original|\n $stderr.puts \" \" + original.rjust(max_original_length) + \" | \" + bit_string\n end\n $stderr.puts\n\n # Print the actual bytes in three forms (bits, base-10 number, and ASCII\n # character), maintaining the alternate coloring so we can see how the\n # original bit groups map to the output bytes.\n $stderr.puts \"Bytes (#{pack.length}):\"\n debug_values.map(&:debug_bits).flatten(1).each_slice(8) do |group|\n padding = \"0\" * (8 - group.length)\n colorized_bits = padding + group.map(&:colorized_bit).reverse.join\n just_the_bits = group.map(&:bit)\n\n # Convert this group of bits into a character\n char = [just_the_bits.map(&:to_s).join].pack(\"b*\")\n\n $stderr.puts \" \" + colorized_bits + \" | \" + char.ord.to_s.ljust(3) + \" | \" + char.inspect\n end\n $stderr.puts\n\n # Print the final packed string, which will be the same as the ASCII\n # characters rendered for the packed bits.\n $stderr.puts \"Packed string (#{pack.length}): #{pack.inspect}\"\n $stderr.puts\n end\n\n DebugValue = Struct.new(:debug_bits, :original)\n DebugBit = Struct.new(:colorized_bit, :bit)\n\n private\n\n def int_to_bits(int, bit_count)\n bits = []\n bit_count.times do\n bits << (int & 0x1)\n int >>= 1\n end\n bits\n end\nend\n\nclass BinUnpacker\n def initialize(packed)\n @bits = packed.unpack(\"b*\").fetch(0).chars.map(&:to_i)\n end\n\n def int32\n int(32)\n end\n\n def int16\n int(16)\n end\n\n def int8\n int(8)\n end\n\n def bits(count)\n bits = @bits[0...count]\n @bits = @bits[count..-1]\n bits\n end\n\n def peek(n)\n @bits[0...n]\n end\n\n def int(bit_count)\n bits, @bits = @bits[0...bit_count], @bits[bit_count..-1]\n int = 0\n bits.reverse.each do |bit|\n int <<= 1\n int |= bit\n end\n int\n end\nend\n" }, { "path": "das-0102-data-compressor-from-scratch/garyzip.rb", "content": "#!/usr/bin/env ruby\n\n# This file was used in Destroy All Software production 0102, \"Data Compressor\n# From Scratch\". It wasn't shown in the screencast, so it's not designed to be\n# as readable as the main code. All of this code is exactly as used in the\n# screencast except for:\n#\n# - This comment.\n# - Calls to `render_tree` and `packer.debug` in the `compress` function, so\n# you can easily run this file and see the debug output from the screencast.\n#\n# To see this work, try the command below. Note that the tree printed by\n# `render_tree` will only work in iTerm 2, or other terminals that support its\n# PNG rendering escape codes. If you're not using iTerm 2, you can comment out\n# the call to `render_tree`.\n#\n# echo -n \"abbcccc\" | ./garyzip.rb compress | hexdump\n#\n# To see how this file was written, visit:\n#\n# https://www.destroyallsoftware.com/screencasts/catalog/data-compressor-from-scratch\n\nrequire \"./rendertree\"\nrequire \"./bin\"\n\ndef compress(original)\n tree = build_tree(original)\n table = build_table(tree)\n packer = BinPacker.new\n\n packer.int32(original.length)\n pack_table(table, packer)\n\n original.bytes.each do |byte|\n bits = look_up_byte(table, byte)\n packer.bits(bits)\n end\n\n render_tree(tree)\n packer.debug\n\n packer.pack\nend\n\ndef decompress(compressed)\n unpacker = BinUnpacker.new(compressed)\n\n data_length = unpacker.int32\n table = unpack_table(unpacker)\n\n data_length.times.map do\n look_up_bits(table, unpacker)\n end.map(&:chr).join\nend\n\ndef build_tree(original)\n bytes = original.bytes\n unique_bytes = bytes.uniq\n\n nodes = unique_bytes.map do |byte|\n Leaf.new(byte, bytes.count(byte))\n end\n\n until nodes.length == 1\n node1 = nodes.delete(nodes.min_by(&:count))\n node2 = nodes.delete(nodes.min_by(&:count))\n nodes << Node.new(node1, node2, node1.count + node2.count)\n end\n\n nodes.fetch(0)\nend\n\ndef build_table(node, path=[])\n if node.is_a? Node\n build_table(node.left, path + [0]) +\n build_table(node.right, path + [1])\n else\n [TableRow.new(node.byte, path)]\n end\nend\n\ndef look_up_byte(table, byte)\n table.each do |row|\n if row.byte == byte\n return row.bits\n end\n end\n\n awoijf\nend\n\n# a = 00\n# b = 01\n# c = 1\n\ndef look_up_bits(table, unpacker)\n table.each do |row|\n if row.bits == unpacker.peek(row.bits.length)\n unpacker.bits(row.bits.length)\n return row.byte\n end\n end\n\n awoijf\nend\n\ndef pack_table(table, packer)\n packer.int8(table.length - 1)\n table.each do |row|\n packer.int8(row.byte)\n packer.int8(row.bits.length)\n packer.bits(row.bits)\n end\nend\n\ndef unpack_table(unpacker)\n table_length = unpacker.int8 + 1\n table_length.times.map do\n byte = unpacker.int8\n bit_count = unpacker.int8\n bits = unpacker.bits(bit_count)\n TableRow.new(byte, bits)\n end\nend\n\nNode = Struct.new(:left, :right, :count)\nLeaf = Struct.new(:byte, :count)\n\nTableRow = Struct.new(:byte, :bits)\n\nif ARGV.fetch(0) == \"compress\"\n $stdout.write(compress($stdin.read))\nelse\n $stdout.write(decompress($stdin.read))\nend\n" }, { "path": "das-0102-data-compressor-from-scratch/imgcat", "content": "#!/bin/bash\n\n# tmux requires unrecognized OSC sequences to be wrapped with DCS tmux;\n# ST, and for all ESCs in to be replaced with ESC ESC. It\n# only accepts ESC backslash for ST.\nfunction print_osc() {\n if [[ $TERM == screen* ]] ; then\n printf \"\\033Ptmux;\\033\\033]\"\n else\n printf \"\\033]\"\n fi\n}\n\n# More of the tmux workaround described above.\nfunction print_st() {\n if [[ $TERM == screen* ]] ; then\n printf \"\\a\\033\\\\\"\n else\n printf \"\\a\"\n fi\n}\n\n# print_image filename inline base64contents\n# filename: Filename to convey to client\n# inline: 0 or 1\n# base64contents: Base64-encoded contents\nfunction print_image() {\n print_osc\n printf '1337;File='\n if [[ -n \"$1\" ]]; then\n printf 'name='`echo -n \"$1\" | base64`\";\"\n fi\n if $(base64 --version 2>&1 | grep GNU > /dev/null)\n then\n BASE64ARG=-d\n else\n BASE64ARG=-D\n fi\n echo -n \"$3\" | base64 $BASE64ARG | wc -c | awk '{printf \"size=%d\",$1}'\n printf \";inline=$2\"\n printf \":\"\n echo -n \"$3\"\n print_st\n printf '\\n'\n}\n\nfunction error() {\n echo \"ERROR: $*\" 1>&2\n}\n\nfunction show_help() {\n echo \"Usage: imgcat filename ...\" 1>& 2\n echo \" or: cat filename | imgcat\" 1>& 2\n}\n\n## Main\n\nif [ -t 0 ]; then\n has_stdin=f\nelse\n has_stdin=t\nfi\n\n# Show help if no arguments and no stdin.\nif [ $has_stdin = f -a $# -eq 0 ]; then\n show_help\n exit\nfi\n\n# Look for command line flags.\nwhile [ $# -gt 0 ]; do\n case \"$1\" in\n -h|--h|--help)\n show_help\n exit\n ;;\n -*)\n error \"Unknown option flag: $1\"\n show_help\n exit 1\n ;;\n *)\n if [ -r \"$1\" ] ; then\n print_image \"$1\" 1 \"$(base64 < \"$1\")\"\n else\n error \"imgcat: $1: No such file or directory\"\n exit 2\n fi\n ;;\n esac\n shift\ndone\n\n# Read and print stdin\nif [ $has_stdin = t ]; then\n print_image \"\" 1 \"$(cat | base64)\"\nfi\n\nexit 0\n" }, { "path": "das-0102-data-compressor-from-scratch/rendertree.rb", "content": "# This file was used in Destroy All Software production 0102, \"Data Compressor\n# From Scratch\". It wasn't shown in the screencast, so it's not designed to be\n# as readable as the main code. All of this code is exactly as used in the\n# screencast except for:\n#\n# - New comments (including this one)\n# - The call to `imgcat` was changed to refer to the `imgcat` script in this\n# directory Previously, it relied on the `imgcat` in my ~/bin directory,\n# which is in $PATH.\n#\n# To see how this file was used to build a data compressor, visit:\n#\n# https://www.destroyallsoftware.com/screencasts/catalog/data-compressor-from-scratch\n\nrequire \"open3\"\n\n# Render a Huffman tree by converting it into Graphviz dot code, then piping\n# the dot into the `dot` command line tool, and finally into the `imgcat`\n# script. This will only work in recent versions of iTerm 2, or any other\n# terminal that supports iTerm 2's PNG rendering escape codes.\ndef render_tree(nodes)\n nodes = [nodes] unless nodes.is_a? Array\n dot = [\n \"digraph {\",\n \"ordering=out\",\n \"dpi=120\",\n nodes.map do |node|\n tree_to_dot(node)\n end,\n \"}\"\n ].flatten.join(\"\\n\")\n rendered = Open3.popen3(\"dot -Tpng | ./imgcat\") do |stdin, stdout, stderr, wait_thr|\n stdin.write(dot)\n stdin.close\n stdout.read\n end\n $stderr.puts(rendered)\nend\n\ndef tree_to_dot(node)\n name = \"node_#{node.object_id}\"\n if node.is_a? Node\n [\n %{#{name}[label=\"(n=#{node.count})\"]},\n %{#{name} -> node_#{node.left.object_id}[label=\"0\"]},\n %{#{name} -> node_#{node.right.object_id}[label=\"1\"]},\n tree_to_dot(node.left),\n tree_to_dot(node.right),\n ].join(\"\\n\")\n else\n [\n %{node_#{node.object_id}[label=\"#{node.byte.chr.gsub(/\"/,'\\\"')}\\n(n=#{node.count})\"]},\n ].join(\"\\n\")\n end\nend\n" }, { "path": "das-0102-data-compressor-from-scratch/tree.dot", "content": "digraph {\n dpi=120\n ordering=out;\n\n # abbcccc\n # 1 a\n # 2 b\n # 4 c\n\n a[label=\"a\\n(n=1)\"]\n b[label=\"b\\n(n=2)\"]\n c[label=\"c\\n(n=4)\"]\n\n n1 [label=\"(n=3)\"]\n n1 -> a [label=0]\n n1 -> b [label=1]\n\n n2 [label=\"(n=7)\"]\n n2 -> n1 [label=0]\n n2 -> c [label=1]\n}\n" } ]