{"id":3121,"date":"2013-08-30T18:27:12","date_gmt":"2013-08-30T09:27:12","guid":{"rendered":"http:\/\/www.techscore.com\/blog\/?p=3121"},"modified":"2018-11-14T16:33:54","modified_gmt":"2018-11-14T07:33:54","slug":"ruby-proc%e3%81%ab%e3%82%88%e3%82%8b%e5%a4%89%e6%95%b0%e3%81%ae%e9%9a%a0%e8%94%bd%e3%81%a8bindng","status":"publish","type":"post","link":"https:\/\/www.techscore.com\/blog\/2013\/08\/30\/ruby-proc%e3%81%ab%e3%82%88%e3%82%8b%e5%a4%89%e6%95%b0%e3%81%ae%e9%9a%a0%e8%94%bd%e3%81%a8bindng\/","title":{"rendered":"Ruby: Proc\u306b\u3088\u308b\u5909\u6570\u306e\u96a0\u853d\u3068bindng"},"content":{"rendered":"<p>\u6700\u8fd1\u66f4\u65b0\u30b5\u30dc\u30ea\u3059\u304e\u306a\u5bfa\u5ca1\u3067\u3059\u3002<\/p>\n<p>\u4eca\u56de\u306fRuby\u306eProc\u306b\u95a2\u3059\u308b\u30c8\u30ea\u30d3\u30a2\u3092\u3054\u7d39\u4ecb\u3057\u307e\u3059\u3002<\/p>\n<h2>JavaScript\u3067\u5909\u6570\u96a0\u853d<\/h2>\n<p>JavaScript\u3067\u306f\u30d7\u30ed\u30d1\u30c6\u30a3\u3092private\u306b\u3057\u3066\u96a0\u3057\u305f\u308a\u3067\u304d\u306a\u3044\u306e\u3067\u3001<br \/>\n\u3069\u3046\u3057\u3066\u3082\u96a0\u853d\u3057\u305f\u3044\u5909\u6570\u306f\u30af\u30ed\u30fc\u30b8\u30e3\u306e\u30ed\u30fc\u30ab\u30eb\u5909\u6570\u306b\u9589\u3058\u8fbc\u3081\u3066\u3057\u307e\u3046\u306e\u304c\u5b9a\u77f3\u3067\u3059\u3002<\/p>\n<pre class=\"lang:javascript decode:true\">function createCounter(start) {\r\n  var count = start || 1;\r\n  return function() { return count++; };\r\n}\r\n\r\nvar c1 = createCounter();\r\nvar c2 = createCounter();\r\n\r\nconsole.log(\"c1: \" + c1()); \/\/ c1: 1\r\nconsole.log(\"c1: \" + c1()); \/\/ c1: 2\r\nconsole.log(\"c2: \" + c2()); \/\/ c2: 1\r\nconsole.log(\"c1: \" + c1()); \/\/ c1: 3<\/pre>\n<p>&nbsp;<\/p>\n<h2>Ruby\u3067\u5909\u6570\u96a0\u853d<\/h2>\n<p>Ruby\u306eprivate\u30e1\u30bd\u30c3\u30c9\u306fsend\u3067\u547c\u3073\u51fa\u305b\u308b\u3057\u3001\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u5909\u6570\u306finstance_variable_get\u3084instance_eval\u3067\u53d6\u308a\u51fa\u305b\u307e\u3059\u3002<br \/>\n\u305d\u3053\u3067\u3001JavaScript\u306e\u4f8b\u3068\u540c\u3058\u3088\u3046\u306blambda\u3092\u4f7f\u3063\u3066\u30ed\u30fc\u30ab\u30eb\u5909\u6570\u306b\u9589\u3058\u8fbc\u3081\u3066\u307f\u307e\u3059\u3002<\/p>\n<pre class=\"lang:ruby decode:true\">def create_counter(count = 1)\r\n  -&gt;{ count.tap{ count += 1 } }\r\nend\r\n\r\nc1 = create_counter\r\nc2 = create_counter\r\n\r\nputs \"c1: #{c1.()}\" # c1: 1\r\nputs \"c1: #{c1.()}\" # c1: 2\r\nputs \"c2: #{c2.()}\" # c2: 1\r\nputs \"c1: #{c1.()}\" # c1: 3<\/pre>\n<p>\u3053\u308c\u3067count\u5909\u6570\u3092\u5916\u304b\u3089\u76f4\u63a5\u53c2\u7167\u3057\u305f\u308a\u51fa\u6765\u306a\u3044\u7b48\u3002<br \/>\n\u307e\u3057\u3066\u3084\u66f8\u304d\u63db\u3048\u308b\u306a\u3093\u3066\u4e0d\u53ef\u80fd\uff01\uff01<\/p>\n<p>\u2026\u2026\u305d\u3046\u601d\u3063\u3066\u3044\u305f\u6642\u671f\u304c\u79c1\u306b\u3082\u3042\u308a\u307e\u3057\u305f\u3002<\/p>\n<p>&nbsp;<\/p>\n<h2>\u96a0\u3059\u3069\u3053\u308d\u304b\u5b88\u308c\u3066\u3059\u3089\u3044\u306a\u304b\u3063\u305f orz<\/h2>\n<p>Proc#binding\u306eeval\u3092\u4f7f\u3048\u3070\u2026\u2026<\/p>\n<pre class=\"lang:ruby decode:true\">c3 = create_counter\r\n\r\nputs \"c3: #{c3.()}\" # c3: 1\r\n\r\nc3.binding.eval('count = 100')\r\n\r\nputs \"c3: #{c3.()}\" # c3: 100\r\nputs \"c3: #{c3.()}\" # c3: 101<\/pre>\n<p>\u306a\u3093\u3068\u3044\u3046\u3053\u3068\u3067\u3057\u3087\u3046\uff01<br \/>\nProc\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u96a0\u3055\u308c\u305f\u30ed\u30fc\u30ab\u30eb\u5909\u6570\u3092\u53d6\u5f97\u3001\u5909\u66f4\u3059\u308b\u3053\u3068\u304c\u51fa\u6765\u3066\u3057\u307e\u3044\u307e\u3059\u3002<\/p>\n<p>\u3082\u3061\u308d\u3093\u3001\u3053\u3093\u306a\u90aa\u60aa\u306a\u884c\u3044\u306f\u8a31\u3055\u308c\u308b\u3079\u304d\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002<br \/>\n\u3067\u3059\u304cProc#binding\u306b\u3082\u4f7f\u3044\u9053\u306f\u3042\u308b\u306e\u3067\u3059\u3002<\/p>\n<p>&nbsp;<\/p>\n<h2>Ruby\u306eDSL\u306b\u3042\u308a\u304c\u3061\u306a\u30d1\u30bf\u30fc\u30f3<\/h2>\n<p>Ruby\u306eDSL\u3067\u306f\u30d6\u30ed\u30c3\u30af\u5185\u3067\u30b0\u30ed\u30fc\u30d0\u30eb\u95a2\u6570\u306e\u3088\u3046\u306b\u30e1\u30bd\u30c3\u30c9\u3092\u547c\u3073\u51fa\u3059\u30a4\u30c7\u30a3\u30aa\u30e0\u304c\u3088\u304f\u4f7f\u308f\u308c\u307e\u3059\u3002<br \/>\nRails\u306e\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u3082\u305d\u306e\u4e00\u4f8b\u3067\u3059\u3002<\/p>\n<pre class=\"lang:ruby decode:true\">MyApp::Application.routes.draw do\r\n  resources :users\r\n  resources :products\r\nend<\/pre>\n<p>&nbsp;<\/p>\n<h2>DSL\u3092\u4f5c\u3063\u3066\u307f\u308b<\/h2>\n<p>\u3053\u306e\u30a4\u30c7\u30a3\u30aa\u30e0\u3092\u4f7f\u3063\u305f\u5358\u7d14\u306aDSL\u3092\u63d0\u4f9b\u3059\u308bGreeter\u30af\u30e9\u30b9\u3092\u4f5c\u3063\u3066\u307f\u307e\u3059\u3002<br \/>\n\u30d6\u30ed\u30c3\u30af\u5185\u3067\u306fgreet\u30e1\u30bd\u30c3\u30c9\u3092\u63d0\u4f9b\u3059\u308b\u3053\u3068\u306b\u3057\u307e\u3059\u3002<\/p>\n<pre class=\"lang:ruby decode:true\">class Greeter\r\n  def greet(name)\r\n    puts \"Hello #{name}!!\"\r\n  end\r\n\r\n  def self.dsl(&amp;block)\r\n    new.instance_eval(&amp;block)\r\n  end\r\nend\r\n\r\nGreeter.dsl do\r\n  greet \"Jiro\" # Hello Jiro!!\"\r\nend\r\n<\/pre>\n<p>\u30d6\u30ed\u30c3\u30af\u5185\u3067greet\u30e1\u30bd\u30c3\u30c9\u3092\u547c\u3073\u51fa\u3059\u3053\u3068\u304c\u51fa\u6765\u307e\u3057\u305f\uff01<\/p>\n<p>Ruby\u306e\u30d6\u30ed\u30c3\u30af\u3001Proc\u306f\u5b9a\u7fa9\u6642\u306e\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9(self)\u3092\u4fdd\u6301\u3057\u3066\u3044\u308b\u305f\u3081\u3001<br \/>\n\u30d6\u30ed\u30c3\u30af\u306e\u4e2d\u3067\u3082\u30a4\u30f3\u30b9\u30bf\u30f3\u5909\u6570\u3084\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u30e1\u30bd\u30c3\u30c9\u3092\u547c\u3073\u51fa\u3059\u3053\u3068\u304c\u51fa\u6765\u307e\u3059\u3002<\/p>\n<p>\u4eca\u56de\u306f\u30d6\u30ed\u30c3\u30af\u5185\u306e\u30e1\u30bd\u30c3\u30c9\u547c\u3073\u51fa\u3057\u3092Greeter\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u306b\u5bfe\u3059\u308b\u547c\u3073\u51fa\u3057\u306b\u5909\u66f4\u3059\u308b\u305f\u3081\u3001<br \/>\ninstance_eval\u306b\u3088\u3063\u3066\u30d6\u30ed\u30c3\u30af\u306eself\u3092\u5dee\u3057\u66ff\u3048\u3066\u5b9f\u884c\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n<p>&nbsp;<\/p>\n<h2>\u5916\u5074\u306e\u30af\u30e9\u30b9\u306e\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u3044\u305f\u3044<\/h2>\n<p>\u3053\u306eDSL\u3092Rails\u306e\u30b3\u30f3\u30c8\u30ed\u30fc\u30e9\u5185\u3067\u4f7f\u3063\u3066\u307f\u305f\u304f\u306a\u3063\u305f\u306e\u3067\u3001params[:name]\u3092\u5f15\u6570\u306b\u6e21\u3057\u3066greet\u30e1\u30bd\u30c3\u30c9\u3092\u547c\u3073\u51fa\u3059\u3053\u3068\u306b\u3057\u307e\u3057\u305f\u3002<\/p>\n<pre class=\"lang:ruby decode:true\">class UsersController &lt; ApplicationController\r\n  def index\r\n    Greeter.dsl do\r\n      greet params[:name] # NameError: undefined local variable or method `params' for #\r\n    end\r\n  end\r\nend<\/pre>\n<p>\u30d6\u30ed\u30c3\u30af\u5185\u306eself\u306fGreeter\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u306b\u5dee\u3057\u66ff\u3048\u3089\u308c\u3066\u3044\u308b\u305f\u3081\u3001UsersController\u306e\u30e1\u30bd\u30c3\u30c9\u3067\u3042\u308bparams\u3092\u547c\u3073\u51fa\u3059\u3053\u3068\u306f\u51fa\u6765\u307e\u305b\u3093\u3002<\/p>\n<p>\u30d6\u30ed\u30c3\u30af\u5185\u3067Greeter\u3068UsersController\u4e21\u65b9\u306e\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u3046\u306b\u306f\u3069\u3046\u3059\u308c\u3070\u3088\u3044\u3067\u3057\u3087\u3046\u304b\uff1f<\/p>\n<p>&nbsp;<\/p>\n<h2>Proc#binding\u3068method_missing\u306e\u5408\u308f\u305b\u6280<\/h2>\n<pre class=\"lang:ruby decode:true\">class Greeter\r\n  def initialize(context)\r\n    @context = context\r\n  end\r\n\r\n  def greet(name)\r\n    puts \"Hello #{name}!!\"\r\n  end\r\n\r\n  def method_missing(name, *args, &amp;block)\r\n    @context.send(name, *args, &amp;block)\r\n  end\r\n\r\n  def self.dsl(&amp;block)\r\n    new(block.binding.eval('self')).instance_eval(&amp;block)\r\n  end\r\nend<\/pre>\n<p>\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf\u3067\u53d7\u3051\u53d6\u3063\u305f\u5f15\u6570(context)\u306b\u5bfe\u3057\u3066\u3001method_missing\u3067send\u3092\u547c\u3076\u3088\u3046\u306b\u306a\u308a\u307e\u3057\u305f\u3002<br \/>\n\u3053\u3046\u3059\u308b\u3068\u3001Greeter\u30af\u30e9\u30b9\u306b\u30e1\u30bd\u30c3\u30c9\u304c\u898b\u3064\u304b\u3089\u306a\u3044\u5834\u5408\u306f@context\u306b\u5bfe\u3059\u308b\u30e1\u30bd\u30c3\u30c9\u547c\u3073\u51fa\u3057\u306b\u5909\u63db\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n<p>\u5f8c\u306f\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf\u306bcontext\u3068\u3057\u3066UsersController\u306e\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u3092\u4e0e\u3048\u308b\u3060\u3051\u3067\u3059\u3002<\/p>\n<p>\u3053\u3053\u3067\u3088\u3046\u3084\u304fProc#binding\u306e\u51fa\u756a\u304c\u3084\u3063\u3066\u6765\u307e\u3057\u305f\u3002<br \/>\nblock.binding.eval('self') \u3092\u547c\u3073\u51fa\u305b\u3070\u3001\u300cblock\u3092\u5b9a\u7fa9\u3057\u305f\u5834\u6240\u3067\u306eself\u300d\u3064\u307e\u308aUsersController\u306e\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u3092\u53d6\u5f97\u3059\u308b\u3053\u3068\u304c\u51fa\u6765\u308b\u306e\u3067\u3059\uff01\uff01<\/p>\n<p>2013\/9\/19 \u8ffd\u8a18\uff1a<br \/>\nBinding#eval('self')\u76f8\u5f53\u306e\u30e1\u30bd\u30c3\u30c9\u304c\u3001ruby2.1\u3067 Binding#receiver \u3068\u3044\u3046\u540d\u524d\u3067\u63a1\u7528\u3055\u308c\u308b\u304b\u3082\u3057\u308c\u307e\u305b\u3093\u3002 <a href=\"http:\/\/bugs.ruby-lang.org\/issues\/8779\">http:\/\/bugs.ruby-lang.org\/issues\/8779<\/a><\/p>\n<pre class=\"lang:ruby decode:true\">class UsersController &lt; ApplicationController\r\n  def index\r\n    Greeter.dsl do\r\n      greet params[:name] # \u30a8\u30e9\u30fc\u306b\u306a\u3089\u305a\u306b\u30ed\u30b0\uff08\u6a19\u6e96\u51fa\u529b\uff09\u306b\u8868\u793a\u3055\u308c\u308b\r\n    end\r\n  end\r\nend<\/pre>\n<p>\u4e00\u898b\u4f7f\u3044\u9053\u306e\u5206\u304b\u3089\u306a\u3044\u30e1\u30bd\u30c3\u30c9\u306b\u3082\u3001\u610f\u5916\u306a\u6d3b\u7528\u6cd5\u304c\u3042\u3063\u305f\u308a\u3059\u308b\u3082\u306e\u3067\u3059\u306d\u3002<\/p>\n<p>Enjoy Ruby!!<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u6700\u8fd1\u66f4\u65b0\u30b5\u30dc\u30ea\u3059\u304e\u306a\u5bfa\u5ca1\u3067\u3059\u3002<\/p>\n<p>\u4eca\u56de\u306fRuby\u306eProc\u306b\u95a2\u3059\u308b\u30c8\u30ea\u30d3\u30a2\u3092\u3054\u7d39\u4ecb\u3057\u307e\u3059\u3002<br \/>\nJavaScript\u3067\u5909\u6570\u96a0\u853d<br \/>\nJavaScript\u3067\u306f\u30d7\u30ed\u30d1\u30c6\u30a3\u3092private\u306b\u3057\u3066\u96a0\u3057\u305f\u308a\u3067\u304d\u306a\u3044\u306e\u3067\u3001<br \/>\n\u3069\u3046\u3057\u3066\u3082\u96a0\u853d\u3057\u305f\u3044\u5909\u6570\u306f\u30af\u30ed\u30fc\u30b8\u30e3\u306e\u30ed\u30fc\u30ab\u30eb\u5909\u6570\u306b\u9589\u3058\u8fbc\u3081\u3066\u3057\u307e\u3046\u306e\u304c\u5b9a\u77f3\u3067\u3059\u3002<br \/><a href=\"https:\/\/www.techscore.com\/blog\/2013\/08\/30\/ruby-proc%e3%81%ab%e3%82%88%e3%82%8b%e5%a4%89%e6%95%b0%e3%81%ae%e9%9a%a0%e8%94%bd%e3%81%a8bindng\/\">\u7d9a\u304d\u3092\u8aad\u3080...<\/a><\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[18],"tags":[107,24],"_links":{"self":[{"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/posts\/3121"}],"collection":[{"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/comments?post=3121"}],"version-history":[{"count":1,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/posts\/3121\/revisions"}],"predecessor-version":[{"id":17914,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/posts\/3121\/revisions\/17914"}],"wp:attachment":[{"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/media?parent=3121"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/categories?post=3121"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/tags?post=3121"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}