{"id":45584,"date":"2023-03-14T13:47:59","date_gmt":"2023-10-23T21:50:03","guid":{"rendered":"https:\/\/www.silicloud.com\/zh\/blog\/45584-2\/"},"modified":"2024-04-29T18:51:33","modified_gmt":"2024-04-29T10:51:33","slug":"45584-2","status":"publish","type":"post","link":"https:\/\/www.silicloud.com\/zh\/blog\/45584-2\/","title":{"rendered":""},"content":{"rendered":"

\u4eca\u5e74\u306e\u8a00\u8a9e\u306fRust \u305d\u306e\uff19<\/h1>\n

Rust\u3092\u5b66\u3073\u307e\u3059<\/p>\n

Rust\u306e\u65e5\u672c\u8a9e\u30c9\u30ad\u30e5\u30e1\u30f3\u30c8 2nd Edition
\nhttps:\/\/doc.rust-jp.rs\/book\/second-edition\/<\/p>\n

\u30aa\u30ea\u30b8\u30ca\u30eb(\u82f1\u8a9e)
\nhttps:\/\/doc.rust-lang.org\/book\/<\/p>\n

6. Enum\u3068\u30d1\u30bf\u30fc\u30f3\u30de\u30c3\u30c1\u30f3\u30b0<\/h2>\n

6.1 Enum\u3092\u5b9a\u7fa9<\/h3>\n
\r\nenum<\/span> IpAddrKind<\/span>{<\/span>\r\n    V4<\/span>,<\/span>\r\n    V6<\/span>,<\/span>\r\n}<\/span>\r\n\r\n\r\nstruct<\/span> IpAddr<\/span>{<\/span>\r\n    kind<\/span>:<\/span> IpAddrKind<\/span>,<\/span>\r\n    address<\/span>:<\/span> String<\/span>,<\/span>\r\n}<\/span>\r\n\r\n\r\nfn<\/span> main<\/span>(){<\/span>\r\n\r\n    let<\/span> home<\/span> =<\/span> IpAddr<\/span>{<\/span>\r\n      kind<\/span>:<\/span> IpAddrKind<\/span>::<\/span>V4<\/span>,<\/span>\r\n      address<\/span>:<\/span> String<\/span>::<\/span>from<\/span>(<\/span>\"192.168.0.1\"<\/span>),<\/span>\r\n    };<\/span>\r\n\r\n    let<\/span> loopback<\/span> =<\/span> IpAddr<\/span>{<\/span>\r\n      kind<\/span>:<\/span> IpAddrKind<\/span>::<\/span>V6<\/span>,<\/span>\r\n      address<\/span>:<\/span> String<\/span>::<\/span>from<\/span>(<\/span>\"::1\"<\/span>),<\/span>\r\n    };<\/span>\r\n}<\/span>\r\n\r\n\r\n\r\n<\/code><\/pre>\n
\u7570\u306a\u308b\u5217\u6319\u5b50\u3092\u542b\u3080enum\u3092\u4f5c\u308c\u308b<\/p>\n
\r\nenum<\/span> Message<\/span>{<\/span>\r\n    Quit<\/span>,<\/span>\r\n    Move<\/span> {<\/span> x<\/span>:<\/span> i32<\/span>,<\/span> y<\/span>:<\/span> i32<\/span>},<\/span>\r\n    Write<\/span>(<\/span>String<\/span>),<\/span>\r\n    ChangeColor<\/span>(<\/span>i32<\/span>,<\/span> i32<\/span>,<\/span> i32<\/span>),<\/span>\r\n}<\/span>\r\n<\/code><\/pre>\n
struct<\/span> QuiteMessage<\/span>;<\/span> \/\/ \u30e6\u30cb\u30c3\u30c8\u69cb\u9020\u4f53<\/span>\r\nstruct<\/span> MoveMessage<\/span>{<\/span>x<\/span>:<\/span> i32<\/span>,<\/span> y<\/span>:<\/span> i32<\/span>}<\/span>\r\nstruct<\/span> WriteMessage<\/span>(<\/span>String<\/span>);<\/span> \/\/ \u30bf\u30d7\u30eb\u69cb\u9020\u4f53<\/span>\r\nstruct<\/span> ChangeColorMessage<\/span>(<\/span>i32<\/span>,<\/span> i32<\/span>,<\/span> i32<\/span>)<\/span> \/\/ \u30bf\u30d7\u30eb\u69cb\u9020\u4f53<\/span>\r\n<\/code><\/pre>\n
c\u8a00\u8a9e\u3068\u3042\u307e\u308a\u5909\u308f\u3089\u306a\u3044\u4f7f\u3044\u65b9\u3002<\/p>\n
enum\u3082\u30e1\u30bd\u30c3\u30c9\u3092\u542b\u3081\u308c\u308b<\/p>\n
#[derive(Debug)]<\/span>\r\n\r\nenum<\/span> Message<\/span>{<\/span>\r\n    Quit<\/span>,<\/span>\r\n    Move<\/span> {<\/span> x<\/span>:<\/span> i32<\/span>,<\/span> y<\/span>:<\/span> i32<\/span>},<\/span>\r\n    Write<\/span>(<\/span>String<\/span>),<\/span>\r\n    ChangeColor<\/span>(<\/span>i32<\/span>,<\/span> i32<\/span>,<\/span> i32<\/span>),<\/span>\r\n}<\/span>\r\n\r\n\r\nimpl<\/span> Message<\/span>{<\/span>\r\n\r\n    fn<\/span> call<\/span>(<\/span>&<\/span>self<\/span>){<\/span>\r\n\r\n    }<\/span>\r\n}<\/span>\r\n\r\n\r\nfn<\/span> main<\/span>(){<\/span>\r\n\r\n    \/\/ enum\u578b<\/span>\r\n    let<\/span> m<\/span> =<\/span> Message<\/span>::<\/span>Write<\/span>(<\/span>String<\/span>::<\/span>from<\/span>(<\/span>\"hello\"<\/span>));<\/span>\r\n\r\n    m<\/span>.call<\/span>();<\/span>\r\n\r\n}<\/span>\r\n<\/code><\/pre>\n
Rust\u306b\u306fnull\u3092\u8a31\u5bb9\u3067\u304d\u308b\u578b\u3068\u305d\u3046\u3067\u306a\u3044\u578b\u304c\u3042\u308b\u3002<\/p>\n
\u3082\u3057\u3001null\u304c\u5165\u308b\u53ef\u80fd\u6027\u306e\u3042\u308b\u5909\u6570\u306b\u306fOption\u3092\u5229\u7528\u3059\u308b\u3072\u3064\u3088\u3046\u304c\u3042\u308b\u3002<\/p>\n
\u4e0d\u6b63\u78ba\u306bnull\u3067\u306a\u3044\u5024\u3092\u60f3\u5b9a\u3059\u308b\u5fc3\u914d\u3092\u3057\u306a\u304f\u3066\u3082\u3088\u3044\u3068\u3044\u3046\u3053\u3068\u306f\u3001\u30b3\u30fc\u30c9\u5185\u3067\u3088\u308a\u81ea\u4fe1\u3092\u6301\u3066\u308b\u3053\u3068\u306b\u306a\u308a\u307e\u3059\u3002 null\u306b\u306a\u308b\u53ef\u80fd\u6027\u306e\u3042\u308b\u5024\u3092\u4fdd\u6301\u3059\u308b\u306b\u306f\u3001\u305d\u306e\u5024\u306e\u578b\u3092Option\u306b\u3059\u308b\u3053\u3068\u3067\u660e\u793a\u7684\u306b\u540c\u610f\u3057\u306a\u3051\u308c\u3070\u306a\u308a\u307e\u305b\u3093\u3002 \u305d\u308c\u304b\u3089\u305d\u306e\u5024\u3092\u4f7f\u7528\u3059\u308b\u969b\u306b\u306f\u3001\u5024\u304cnull\u3067\u3042\u308b\u5834\u5408\u3092\u660e\u793a\u7684\u306b\u51e6\u7406\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002 \u5024\u304cOption\u4ee5\u5916\u306e\u578b\u3067\u3042\u308b\u3068\u3053\u5168\u3066\u306b\u304a\u3044\u3066\u3001\u5024\u304cnull\u3067\u306a\u3044\u3068\u5b89\u5168\u306b\u60f3\u5b9a\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002 \u3053\u308c\u306f\u3001Rust\u306b\u3068\u3063\u3066\u3001\u610f\u56f3\u7684\u306a\u8a2d\u8a08\u4e0a\u306e\u6c7a\u5b9a\u3067\u3042\u308a\u3001null\u306e\u666e\u904d\u6027\u3092\u5236\u9650\u3057\u3001Rust\u30b3\u30fc\u30c9\u306e\u5b89\u5168\u6027\u3092\u5411\u4e0a\u3055\u305b\u307e\u3059\u3002<\/p><\/blockquote>\n
\u3064\u307e\u308a\u901a\u5e38\u306e\u578b\u306fnull\u306f\u8a31\u5bb9\u3055\u308c\u306a\u3044\u3002<\/p>\n
\r\nenum<\/span> Option<\/span><<\/span>T<\/span>><\/span>{<\/span>\r\n    Some<\/span>(<\/span>T<\/span>),<\/span>\r\n    None<\/span>,<\/span>\r\n}<\/span>\r\n\r\nfn<\/span> main<\/span>(){<\/span>\r\n\r\n    let<\/span> x<\/span>:<\/span> i8<\/span> =<\/span> 5<\/span>;<\/span>\r\n    let<\/span> y<\/span>:<\/span> Option<\/span><<\/span>i8<\/span>><\/span> =<\/span> Some<\/span>(<\/span>5<\/span>);<\/span>\r\n\r\n    let<\/span> sum<\/span> =<\/span> x<\/span> +<\/span> y<\/span>;<\/span>\r\n\r\n}<\/span>\r\n\r\nerror<\/span>[<\/span>E0277<\/span>]:<\/span> cannot<\/span> add<\/span> `<\/span>std<\/span>::<\/span>option<\/span>::<\/span>Option<\/span><<\/span>i8<\/span>><\/span>`<\/span> to<\/span> `<\/span>i8<\/span>`<\/span>\r\n -<\/span>-><\/span> src<\/span>\/<\/span>main<\/span>.rs<\/span>:<\/span>8<\/span>:<\/span>17<\/span>\r\n  |<\/span>\r\n8<\/span> |<\/span>     let<\/span> sum<\/span> =<\/span> x<\/span> +<\/span> y<\/span>;<\/span>\r\n  |<\/span>                 ^<\/span> no<\/span> implementation<\/span> for<\/span> `<\/span>i8<\/span> +<\/span> std<\/span>::<\/span>option<\/span>::<\/span>Option<\/span><<\/span>i8<\/span>><\/span>`<\/span>\r\n  |<\/span>\r\n  =<\/span> help<\/span>:<\/span> the<\/span> trait<\/span> `<\/span>std<\/span>::<\/span>ops<\/span>::<\/span>Add<\/span><<\/span>std<\/span>::<\/span>option<\/span>::<\/span>Option<\/span><<\/span>i8<\/span>>><\/span>`<\/span> is<\/span> not<\/span> implemented<\/span> for<\/span> `<\/span>i8<\/span>`<\/span>\r\n\r\n<\/code><\/pre>\n
\u7406\u89e3\u3057\u305f\uff01<\/p>\n
\u6b21\u56de\uff01<\/p>\n
\u30a4\u30a8\u30b9\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"
\u4eca\u5e74\u306e\u8a00\u8a9e\u306fRust \u305d\u306e\uff19 Rust\u3092\u5b66\u3073\u307e\u3059 Rust\u306e\u65e5\u672c\u8a9e\u30c9\u30ad\u30e5\u30e1\u30f3\u30c8 2nd Edition htt […]<\/p>\n","protected":false},"author":9,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-45584","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"yoast_head":"\n- Blog - Silicon Cloud<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.silicloud.com\/zh\/blog\/45584-2\/\" \/>\n<meta property=\"og:locale\" content=\"zh_CN\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:description\" content=\"\u4eca\u5e74\u306e\u8a00\u8a9e\u306fRust \u305d\u306e\uff19 Rust\u3092\u5b66\u3073\u307e\u3059 Rust\u306e\u65e5\u672c\u8a9e\u30c9\u30ad\u30e5\u30e1\u30f3\u30c8 2nd Edition htt […]\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.silicloud.com\/zh\/blog\/45584-2\/\" \/>\n<meta property=\"og:site_name\" content=\"Blog - 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