{"id":6563,"date":"2014-10-24T11:25:39","date_gmt":"2014-10-24T02:25:39","guid":{"rendered":"http:\/\/www.moonmile.net\/blog\/?p=6563"},"modified":"2014-10-25T18:53:03","modified_gmt":"2014-10-25T09:53:03","slug":"f-%e3%81%ae%e5%88%a4%e5%88%a5%e5%85%b1%e7%94%a8%e5%af%be%e3%82%92-c-%e3%81%a7%e4%bd%bf%e3%81%84%e3%82%84%e3%81%99%e3%81%84%e3%82%88%e3%81%86%e3%81%ab%e3%82%ad%e3%83%a3%e3%82%b9%e3%83%88%e3%81%99","status":"publish","type":"post","link":"http:\/\/www.moonmile.net\/blog\/archives\/6563","title":{"rendered":"F# \u306e\u5224\u5225\u5171\u7528\u4f53\u3092 C# \u3067\u4f7f\u3044\u3084\u3059\u3044\u3088\u3046\u306b\u30ad\u30e3\u30b9\u30c8\u3059\u308b"},"content":{"rendered":"

F# \u3067 lex\/yacc \u3063\u307d\u3044\u3082\u306e\u3092\u4f5c\u3063\u3066\u3044\u308b\u3068\u5224\u5225\u5171\u7528\u4f53\uff08Discriminated Unions\uff09\u304c\u4fbf\u5229\u306a\u306e\u3067\u3001\u3088\u304f\u4f7f\u3046\u306e\u3067\u3046\u306e\u3067\u3059\u304c\u300cC# \u3067\u4f7f\u3046\u6642\u306f\u3069\u3046\u3059\u308b\u306e\u304b\uff1f\u300d\u3068\u805e\u304b\u308c\u3066\u3001\u306f\u3066\uff1f\u3068\u601d\u3063\u3066\u3057\u307e\u3044\u307e\u3057\u305f\u3002Xamarin.Forms \u306e\u30d1\u30fc\u30b5\u3092\u4f5c\u3063\u3066\u3044\u308b\u3068\u304d\u306f\u3001\u305d\u306e\u3042\u305f\u308a\u306f\u5fae\u5999\u306b\u907f\u3051\u3066\uff08\u3088\u304f\u308f\u304b\u3089\u306a\u304b\u3063\u305f\u306e\u3067\uff09C# \u304b\u3089\u306f\u76f4\u63a5\u5224\u5225\u5171\u7528\u4f53\u3092\u4f7f\u308f\u306a\u3044\u3088\u3046\u306a\u5de5\u592b\u3092\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n

\u304c\u3001Optional \u3092\u4f7f\u3063\u305f\u308a Choice \u3092\u4f7f\u3063\u305f\u308a\u3059\u308b\u3068\uff08\u79c1\u81ea\u8eab\u306f\u4f7f\u3063\u3066\u306a\u3044\u3051\u3069\uff09\u3001\u3053\u306e\u3042\u305f\u308a\u306f\u3069\u3046\u3059\u308b\u306e\u304b\uff1f\u3063\u3066\u8a71\u3067\u3059\u3002<\/p>\n

\u5224\u5225\u5171\u7528\u4f53\u3092\u4f5c\u308b<\/h2>\n

\u4ed6\u306e\u5834\u5408\u3082\u4e00\u7dd2\u3060\u3068\u601d\u3046\u306e\u3067\u3001\u5143\u30cd\u30bf\u306e\u5224\u5225\u5171\u7528\u4f53\u3092\u4f5c\u308a\u307e\u3059\u3002C\/C++ \u3067\u8a00\u3048\u3070 union \u306a\u306e\u3067\u3001\u305d\u3093\u306a\u306b\u9055\u548c\u611f\u306f\u3042\u308a\u307e\u305b\u3093\u3002<\/p>\n

\r\ntype A =\r\n    | STR of string\r\n    | INT of int\r\n    | KEYVALUE of key:string * value:string\r\n<\/pre>\n
\u5224\u5225\u5171\u7528\u4f53\u3092\u4f7f\u3046<\/h2>\n
\u5224\u5225\u5171\u7528\u4f53\u304c\u4fbf\u5229\u306a\u306e\u306f\u3001\u5229\u7528\u3059\u308b\u3068\u304d\u306b match \u3067\u5224\u65ad\u3067\u304d\u308b\u3068\u3053\u308d\u3067\u3059\u3002C\/C++ \u306e union \u306e\u5834\u5408\u306f type \u3092\u5185\u90e8\u306b\u6301\u305f\u305b\u308b\u3060\u308d\u3046\u3057\u3001Variant \u306e\u5834\u5408\u3082\u4f3c\u305f\u308a\u5bc4\u3063\u305f\u308a\u3067\u3059\u3002\u30e1\u30e2\u30ea\u52b9\u7387\u306f\u3069\u3046\u306a\u306e\u304b\u306f\u6c17\u306b\u306a\u308b\u3068\u3053\u308d\u3067\u3059\u304c\u3001\u305d\u306e\u3042\u305f\u308a\u306f .NET \u306a\u306e\u3067\u3001\u5225\u3005\u306b\u6301\u3063\u3066\u3044\u308b\u306e\u304b\u3082\u3002<\/p>\n
\r\nlet go() =\r\n    let message a =\r\n        let msg =\r\n            match a with\r\n            | A.STR(s) -> &quot;string is &quot; + s\r\n            | A.INT(i) -> &quot;int is &quot; + i.ToString()\r\n            | A.KEYVALUE(k,v) -> &quot;pair is &quot; + k + &quot;, &quot; + v\r\n        printfn &quot;%A&quot; msg\r\n\r\n    let a = A.STR(&quot;masuda&quot;)\r\n    message a\r\n    let b = A.KEYVALUE(&quot;address&quot;,&quot;itabashi&quot;)\r\n    message b\r\n<\/pre>\n
\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u4f5c\u308b\u3068\u304d\u306f\u3001A.STR \u3042\u308b\u3044\u306f STR \u3067\u4f5c\u308c\u3066\u3001\u30c1\u30a7\u30c3\u30af\u3059\u308b\u3068\u304d\u306f match \u3067\u5224\u5225\u3057\u307e\u3059\u3002\u4fbf\u5229\u3067\u3059\u306d\u3002
\n\u3053\u308c\u304c\u3069\u306e\u304f\u3089\u3044\u4fbf\u5229\u304b\u3068\u3044\u3046\u3068\u3001C# \u306b\u66f8\u3044\u3066\u307f\u308b\u3068\u308f\u304b\u308a\u307e\u3059\u3002<\/p>\n
C#\u3067\u5224\u5225\u5171\u7528\u5bfe\u3092\u4f7f\u3046<\/h2>\n
\u307e\u305a\u3001A.STR \u306e\u5834\u5408\u304c\u305d\u306e\u307e\u307e\u4f7f\u3048\u306a\u3044\u306e\u3067\u3001create \u306e\u305f\u3081\u306e\u30e1\u30bd\u30c3\u30c9\u3092\u4f5c\u3063\u3066\u304a\u304d\u307e\u3059\u3002
\nFactory \u30d1\u30bf\u30fc\u30f3\u3067\u3001create \u3057\u307e\u3059\u3002<\/p>\n
\r\ntype A =\r\n    | STR of string\r\n    | INT of int\r\n    | KEYVALUE of key:string * value:string\r\n\r\n    \/\/ C# \u306e\u305f\u3081\u306e create\r\n    static member create(s:string) = STR(s)\r\n    static member create(i:int) = INT(i)\r\n    static member create(k:string, v:string) = KEYVALUE(k,v)\r\n<\/pre>\n
\u3053\u308c\u3067\u3001C# \u304b\u3089\u4f5c\u6210\u3059\u308b\u3068\u304d\u306f\u3001create \u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u3048\u3070\u3088\u3044\u3053\u3068\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n
\r\nvar a = A.create("masuda");\r\n<\/pre>\n
F# \u306e match \u306e\u90e8\u5206\u306f\u3069\u3046\u306a\u308b\u304b\u3068\u3044\u3046\u3068\u3001\u7d50\u69cb\u9762\u5012\u3067\u3059\u3002
\n\u3053\u308c\u306f\u3001\u5224\u5225\u5171\u7528\u4f53 A \u30af\u30e9\u30b9\u306e\u5185\u5bb9\u3092\u30b3\u30f3\u30bd\u30fc\u30eb\u306b\u51fa\u529b\u3057\u3066\u3044\u308b\u3060\u3051\u306a\u306e\u3067\u3059\u304c\u3001IsSTR \u30d7\u30ed\u30d1\u30c6\u30a3\u3067\u30c1\u30a7\u30c3\u30af\u3092\u3057\u305f\u5f8c\u306b\u3001A.STR \u3067\u30ad\u30e3\u30b9\u30c8\u3057\u306a\u3044\u3068\u3044\u3051\u307e\u305b\u3093\u3002<\/p>\n
\r\nstatic void debug( DiscrUnion.A a )\r\n{\r\n    if (a.IsSTR)\r\n    {\r\n        string s = (a as A.STR).Item;\r\n        Console.WriteLine("string is {0}", s);\r\n    }\r\n    else if (a.IsINT)\r\n    {\r\n        int i = (a as A.INT).Item;\r\n        Console.WriteLine("int is {0}", i);\r\n    } else if ( a.IsKEYVALUE )\r\n    {\r\n        string k = (a as A.KEYVALUE).key;\r\n        string v = (a as A.KEYVALUE).value;\r\n        Console.WriteLine("pair is {0}, {1}", k, v);\r\n    }\r\n    else\r\n    {\r\n        Console.WriteLine("error");\r\n    }\r\n}\r\n<\/pre>\n
F# \u306e match \u306b\u6bd4\u3079\u308b\u3068\u304b\u306a\u308a\u5197\u9577\u306a\u611f\u3058\u3067\u3059\u3002<\/p>\n
\u3053\u308c\u304c\u9762\u5012\u306a\u306e\u3067\u3001C# \u306b\u5224\u5225\u5171\u7528\u4f53\u30af\u30e9\u30b9\u3092\u516c\u958b\u3059\u308b\u306e\u306f\u3084\u3081\u3066\u3044\u305f\u306e\u3067\u3059\u304c\u3001\u3069\u3046\u3057\u3066\u3082\u516c\u958b\u3059\u308b\u5fc5\u8981\u304c\u3042\u308b\u306a\u3089\u3070\u3001\u30ad\u30e3\u30b9\u30c8\u3092\u4f5c\u308c\u3070\u3088\u304b\u308d\u3046\u3001\u3063\u3066\u3053\u3068\u306b\u5148\u65e5\u6c17\u3065\u304d\u307e\u3057\u305f\u3002
\nF# \u3067\u3082 op_Explicit \u3084 op_Implicit \u30e1\u30bd\u30c3\u30c9\u3092\u66f8\u304f\u3053\u3068\u306b\u3088\u3063\u3066\u3001\u660e\u793a\u7684\u306a\u30ad\u30e3\u30b9\u30c8\u3068\u6697\u9ed9\u306e\u30ad\u30e3\u30b9\u30c8\u3092\u4f5c\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n
C# \u306b\u516c\u958b\u3059\u308b\u30ad\u30e3\u30b9\u30c8\u30e1\u30bd\u30c3\u30c9\u3092\u4f5c\u308b<\/h2>\n
\r\ntype A =\r\n    | STR of string\r\n    | INT of int\r\n    | KEYVALUE of key:string * value:string\r\n\r\n    \/\/ C# \u306e\u305f\u3081\u306e create\r\n    static member create(s:string) = STR(s)\r\n    static member create(i:int) = INT(i)\r\n    static member create(k:string, v:string) = KEYVALUE(k,v)\r\n\r\n    \/\/ C# \u306e\u305f\u3081\u306e\u660e\u793a\u7684\u306a\u30ad\u30e3\u30b9\u30c8\u7528\r\n    static member op_Explicit (a:A) : string =\r\n        match a with\r\n        | A.STR(s) -> s\r\n        | _ -> &quot;&quot;\r\n    static member op_Explicit (a:A) : int =\r\n        match a with\r\n        | A.INT(i) -> i\r\n        | _ -> 0\r\n    static member op_Explicit (a:A) : System.Tuple<string,string> =\r\n        match a with\r\n        | A.KEYVALUE(k,v) -> new System.Tuple<string,string>(k,v)\r\n        | _ -> new System.Tuple<string,string>(&quot;&quot;,&quot;&quot;)\r\n\r\n    \/\/ \u3053\u3063\u3061\u306e\u307b\u3046\u304c\u4fbf\u5229\r\n    member this.ToKeyValue(): System.Tuple<string,string> =\r\n        match this with\r\n        | A.KEYVALUE(k,v) -> new System.Tuple<string,string>(k,v)\r\n        | _ -> new System.Tuple<string,string>(&quot;&quot;,&quot;&quot;)\r\n<\/pre>\n
op_Explicit \u30e1\u30bd\u30c3\u30c9\u3092\u4f5c\u3063\u3066\u304a\u304f\u3068 C# \u3067 (string)a \u306e\u3088\u3046\u306b\u660e\u793a\u7684\u306b\u30ad\u30e3\u30b9\u30c8\u3057\u305f\u3068\u304d\u3068\u540c\u3058\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n
\r\nvar a = A.create("masuda");\r\nstring aa = (string)a;\r\n<\/pre>\n
\u3044\u3061\u3044\u3061\u3001IsSTR \u3067\u30c1\u30a7\u30c3\u30af\u3057\u306a\u304f\u3066\u3088\u3044\u306e\u3067\u3001\u3053\u308c\u3067\u3088\u3055\u305d\u3046\u3067\u3059\u306d\u3002\u5148\u306e op_Explicit \u30e1\u30bd\u30c3\u30c9\u3067\u306f string \u4ee5\u5916\u306e\u3068\u304d\u306f “” \u3067\u7a7a\u6587\u5b57\u5217\u3092\u8fd4\u3057\u3066\u3044\u307e\u3059\u304c\u3001failwith \u306b\u3057\u3066\u4f8b\u5916\u306b\u3057\u3066\u3082\u3088\u3044\u3067\u3057\u3087\u3046\u3002<\/p>\n
KeyValue \u306e\u3088\u3046\u306a Tuple \u3092\u8fd4\u3059\u6642\u306b\u306f\u3001F# \u306e\u3082\u306e\u3092\u8fd4\u3057\u3066\u3082\u826f\u3044\u306e\u3067\u3059\u304c\u3001System.Tuple \u306b\u66f8\u304d\u76f4\u3057\u3066\u3044\u307e\u3059\u3002\u3053\u306e\u305f\u3081\u3001\u30ad\u30e3\u30b9\u30c8\u81ea\u4f53\u304c\u9762\u5012\u3067\u3001\u4e0b\u8a18\u306a\u3053\u3068\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n
\r\nvar b = A.create(&quot;name&quot;, &quot;tomoaki&quot;);\r\nvar bb = (Tuple<string, string>)b;\r\nConsole.WriteLine(&quot;bb is tuple {0}, {1}&quot;, bb.Item1, bb.Item2);\r\n<\/pre>\n
\u578b\u63a8\u8ad6\u306e var \u3067\u53d7\u3051\u308c\u3070\u3088\u3044\u306e\u3067\u306f\uff1f\u3068\u601d\u3046\u3068\u3053\u308d\u3067\u3059\u304c\u3001var \u3067\u53d7\u3051\u3066\u3057\u307e\u3046\u3068\u5224\u5225\u5171\u7528\u4f53\u306e A \u30af\u30e9\u30b9\u306e\u307e\u307e\u306b\u306a\u308b\u306e\u3067\u90fd\u5408\u304c\u60aa\u3044\u306e\u3067\u3059\u3002
\n\u3053\u3046\u3044\u3046\u5834\u5408\u306f\u3001\u7d20\u76f4\u306b ToKeyValue \u30e1\u30bd\u30c3\u30c9\u3092\u4f5c\u3063\u3066\u3001\u30a4\u30f3\u30c6\u30ea\u30bb\u30f3\u30b9\u3092\u52b9\u304b\u305b\u305f\u307b\u3046\u304c\u5206\u304b\u308a\u3084\u3059\u3044\u3067\u3057\u3087\u3046\u3002<\/p>\n
as \u3067\u306f\u30ad\u30e3\u30b9\u30c8\u3067\u304d\u306a\u3044<\/h2>\n
\u5b9f\u306f\u3001\u3072\u3068\u3064\u843d\u3068\u3057\u7a74\u304c\u3042\u3063\u3066\u3001a as string \u306e\u3088\u3046\u306a\u30ad\u30e3\u30b9\u30c8\u306f\u3067\u304d\u307e\u305b\u3093\u3002\u5909\u6570 a \u306f A \u30af\u30e9\u30b9\u306a\u306e\u3067\u3001as \u3067 Type \u30c1\u30a7\u30c3\u30af\u3092\u3059\u308b\u3068 A \u81ea\u8eab\u304c\u8fd4\u3063\u3066\u304f\u308b\u305f\u3081\u3067\u3059\u3002\u306a\u306e\u3067\u3001(string)a \u306e\u3088\u3046\u306b\u300c\u660e\u793a\u7684\u306b\u30ad\u30e3\u30b9\u30c8\u300d\u3092\u3057\u306a\u3044\u3068\u3044\u3051\u306a\u3044\u3068\u3044\u3046\u7f60\u306b\u9665\u308a\u307e\u3059\u3002\u3053\u306e\u3042\u305f\u308a\u306f\u3001\u30ed\u30fc\u30ab\u30eb\u30eb\u30fc\u30eb\u3068\u3044\u3046\u3053\u3068\u3067\u3001\u8981\u6ce8\u610f\u3067\u3059\u3002<\/p>\n
\u3042\u3068\u3001\u6697\u9ed9\u306e\u30ad\u30e3\u30b9\u30c8\u3092\u4f5c\u308d\u3046\u3068\u3059\u308b\u3068\u300c\u6697\u9ed9\u306e\u30ad\u30e3\u30b9\u30c8\u300d\u4ee5\u5916\u304c\u3067\u304d\u306a\u304f\u306a\u308a\u307e\u3059\u3002\u5148\u306e op_Explicit \u3092 op_Implict \u306b\u66f8\u304d\u63db\u3048\u308b\u3068\u3001\u6697\u9ed9\u306e\u30ad\u30e3\u30b9\u30c8\u306b\u306a\u3063\u3066 (string) \u90e8\u5206\u304c\u8981\u3089\u306a\u304f\u3066\u4fbf\u5229\u305d\u3046\u306a\u306e\u3067\u3059\u304c\u3001\u9006\u306b (string) \u3092\u4ed8\u3051\u308b\u3068\u30b3\u30f3\u30d1\u30a4\u30eb\u30a8\u30e9\u30fc\u306b\u306a\u308b\u3001\u3068\u3044\u3046\u4e0d\u601d\u8b70\u306a\u3053\u3068\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n
\r\n\/\/ \u6697\u9ed9\u306e\u30ad\u30e3\u30b9\u30c8\u3092\u4f7f\u3046\r\nstring aa = a;\r\n<\/pre>\n
\u3053\u308c\u306f\u3053\u308c\u3067\u3001var \u304c\u4f7f\u3048\u306a\u304f\u306a\u308b\u306e\u3067\u4e0d\u4fbf\u306a\u611f\u3058\u3067\u3059\u3088\u306d\u3002\u307e\u305f\u3001op_Explicit \u3068 op_Implict \u306f\u540c\u6642\u306b\u5b9a\u7fa9\u3067\u304d\u306a\u3044\u306e\u3067\u3001\u3069\u3061\u3089\u304b\u4e00\u65b9\u3060\u3051\u3092\u4f7f\u3046\u3053\u3068\u306b\u306a\u308a\u307e\u3059\u3002\u3053\u308c\u3082\u5909\u306a\u4ed5\u69d8\u3067\u3059\u304c\u3001\u307e\u3042\u3001\u305d\u306e\u3042\u305f\u308a\u3082\u542b\u3081\u3066\u6ce8\u610f\u3057\u3066\u4f5c\u308b\u3068\u3001\u3046\u307e\u304f C# \u3067\u4f7f\u3048\u308b\u5224\u5225\u5171\u7528\u4f53\u304c\u4f5c\u308c\u307e\u3059\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
F# \u3067 lex\/yacc \u3063\u307d\u3044\u3082\u306e\u3092\u4f5c\u3063\u3066\u3044\u308b\u3068\u5224\u5225\u5171\u7528\u4f53\uff08Discriminated Unions\uff09\u304c\u4fbf\u5229\u306a\u306e\u3067\u3001\u3088\u304f\u4f7f\u3046\u306e\u3067\u3046\u306e\u3067\u3059\u304c\u300cC# \u3067\u4f7f\u3046\u6642\u306f\u3069\u3046\u3059\u308b\u306e\u304b\uff1f\u300d\u3068\u805e\u304b\u308c\u3066\u3001\u306f\u3066\uff1f\u3068\u601d\u3063\u3066\u3057\u307e\u3044\u307e\u3057\u305f\u3002Xa … \u7d9a\u304d\u3092\u8aad\u3080 →<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[23,59],"tags":[],"class_list":["post-6563","post","type-post","status-publish","format-standard","hentry","category-csharp","category-f"],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"http:\/\/www.moonmile.net\/blog\/wp-json\/wp\/v2\/posts\/6563","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.moonmile.net\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.moonmile.net\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.moonmile.net\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"http:\/\/www.moonmile.net\/blog\/wp-json\/wp\/v2\/comments?post=6563"}],"version-history":[{"count":3,"href":"http:\/\/www.moonmile.net\/blog\/wp-json\/wp\/v2\/posts\/6563\/revisions"}],"predecessor-version":[{"id":6585,"href":"http:\/\/www.moonmile.net\/blog\/wp-json\/wp\/v2\/posts\/6563\/revisions\/6585"}],"wp:attachment":[{"href":"http:\/\/www.moonmile.net\/blog\/wp-json\/wp\/v2\/media?parent=6563"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.moonmile.net\/blog\/wp-json\/wp\/v2\/categories?post=6563"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.moonmile.net\/blog\/wp-json\/wp\/v2\/tags?post=6563"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}