{"author_url":"https://blog.hatena.ne.jp/factal/","author_name":"factal","url":"https://factal.hatenadiary.org/entry/20120825/1345886444","version":"1.0","published":"2012-08-25 18:20:44","html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Ffactal.hatenadiary.org%2Fentry%2F20120825%2F1345886444\" title=\"\u3059\u3054\u3044Haskell8\u7ae0 - \u3046\u304a\u3063\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>","title":"\u3059\u3054\u3044Haskell8\u7ae0","provider_url":"https://hatena.blog","height":"190","image_url":null,"provider_name":"Hatena Blog","blog_url":"https://factal.hatenadiary.org/","blog_title":"\u3046\u304a\u3063","width":"100%","type":"rich","categories":["Haskell"],"description":"\u30a2\u30af\u30b7\u30e7\u30f3\u3068\u578b\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf \u30a2\u30af\u30b7\u30e7\u30f3\u3068\u578b\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf\u306e\u9055\u3044\u3063\u3066\u4f55\u3060\u308d\u3046\u3002\u3042\u3068\u3001\u3069\u3046\u3084\u3063\u3066\u533a\u5225\u3059\u308b\u3093\u3060\u308d\u3046\u3002 \u4f8b\u3048\u3070 getLine \u306e\u578b\u3092\u898b\u3066\u307f\u308b\u3002 ghci> :t getLine getLine :: IO String \u3053\u308c\u3063\u3066\u3001\u578b\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf IO \u304c\u3001\u5177\u4f53\u578b String \u3092\u53d7\u3051\u53d6\u3063\u305f\u578b\u306b\u898b\u3048\u308b\u3002 \u7a2e\u985e\u3082\u578b\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf\u3068\u540c\u3058\u3060\u3057\u3002 ghci> :k IO IO :: * -> * ghci> :k Maybe Maybe :: * -> * \u307e\u305f\u5f8c\u3067\u89e3\u8aac\u304c\u51fa\u3066\u304f\u308b\u306e\u304b\u306a\u3002 \uff08\u8ffd\u8a18\uff09\u51fa\u3066\u304d\u305f\u3002 I/O \u30a2\u30af\u30b7\u30e7\u30f3\u304c\u7279\u5225\u306a\u306e\u306f\u3001 main \u95a2\u6570\u306e\u4e2d\u306b\u5165\u3063\u3066\u3044\u308b\u3068\uff08\u3042\u308b\u3044\u306f GH\u2026"}