{"width":"100%","image_url":null,"author_url":"https://blog.hatena.ne.jp/ytqwerty/","version":"1.0","type":"rich","blog_title":"Note","blog_url":"https://ytqwerty.hatenadiary.org/","description":"\u30a2\u30c3\u30d7\u30ad\u30e3\u30b9\u30c8/\u30c0\u30a6\u30f3\u30ad\u30e3\u30b9\u30c8\u306e\u30e1\u30e2\u3002 # type super = [`a | `b | `c];; type super = [ `a | `b | `c ] # type sub = [`a | `b];; type sub = [ `a | `b ] # ((`a : sub) :> super);; - : super = `a # match (`a: super) with #sub as x -> x | `c -> assert false;; - : [> sub ] = `a \u3084\u306f\u308a\u79c1\u306f\u90e8\u5206\u7bc4\u56f2\u578b\u304c\u5927\u597d\u304d\u306a\u3093\u3060\u306a\u3042\u3068\u5b9f\u611f\u4e2d\u3002Pascal\u3068\u7570\u306a\u308a\u5ba3\u8a00\u4e0a\u3067\u9023\u7d9a\u3057\u3066\u3044\u308b\u5fc5\u8981\u304c\u7121\u2026","categories":["OCaml"],"title":" \u591a\u76f8\u30d0\u30ea\u30a2\u30f3\u30c8","height":"190","author_name":"ytqwerty","url":"https://ytqwerty.hatenadiary.org/entry/20090207/p1","published":"2009-02-07 00:00:00","provider_url":"https://hatena.blog","provider_name":"Hatena Blog","html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Fytqwerty.hatenadiary.org%2Fentry%2F20090207%2Fp1\" title=\" \u591a\u76f8\u30d0\u30ea\u30a2\u30f3\u30c8 - Note\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>"}