{"id":45271,"date":"2023-11-13T06:36:54","date_gmt":"2023-11-27T11:25:35","guid":{"rendered":"https:\/\/www.silicloud.com\/zh\/blog\/45271-2\/"},"modified":"2024-05-04T08:48:40","modified_gmt":"2024-05-04T00:48:40","slug":"45271-2","status":"publish","type":"post","link":"https:\/\/www.silicloud.com\/zh\/blog\/45271-2\/","title":{"rendered":""},"content":{"rendered":"

Rust\u306econst fn
\nRust\u306econst fn\u3067abs
\nRust\u306econst fn\u306e\u5236\u9650\u304c\u7de9\u548c\u3055\u308c\u305f(Rust 1.33.0)
\nRust 1.39.0\u3067abs\u304cconst fn\u306b\u306a\u308b
\n\u4e0a\u8a18\u306e\u8a18\u4e8b\u306e\u95a2\u9023\u30fb\u7d9a\u304d\u307f\u305f\u3044\u306a\u3082\u306e\u3067\u3059\u3002<\/p>\n

Rust\u306econst fn\u306e\u5236\u9650\u304c\u3055\u3089\u306b\u7de9\u548c\u3055\u308c\u305f<\/h1>\n

Rust 1.46.0\u3067const fn\u306e\u5236\u9650\u304c\u66f4\u306b\u7de9\u548c\u3055\u308c\u307e\u3057\u305f\u3002<\/p>\n

\u5909\u66f4\u5185\u5bb9<\/h2>\n

\u4e0b\u8a18\u304c\u4f7f\u7528\u3067\u304d\u308b\u3088\u3046\u306b\u306a\u308a\u307e\u3057\u305f
\n– if, if let, match
\n– while, while let, loop
\n– &&\u6f14\u7b97\u5b50, ||\u6f14\u7b97\u5b50<\/p>\n

for\u306f\u4f7f\u7528\u3067\u304d\u306a\u3044\u307e\u307e\u3067\u3059\u304c\u5909\u6570\u306f\u4f7f\u7528\u3067\u304d\u308b\u306e\u3067\u307b\u307c\u666e\u901a\u306e\u95a2\u6570\u3068\u5909\u308f\u3089\u306a\u3044\u66f8\u304d\u65b9\u304c\u3067\u304d\u308b\u3088\u3046\u306b\u306a\u308a\u307e\u3057\u305f\u3002<\/p>\n

for\u306f\u4f7f\u7528\u3067\u304d\u306a\u3044<\/h3>\n

\u4e0a\u3067\u66f8\u304d\u307e\u3057\u305f\u304cfor\u306f\u4f7f\u7528\u3067\u304d\u307e\u305b\u3093\u3002
\n\u3057\u304b\u3057\u5909\u6570\u306f\u4f7f\u7528\u3067\u304d\u308b\u306e\u3067n\u56de\u30eb\u30fc\u30d7\u307f\u305f\u3044\u306a\u3053\u3068\u306fwhile\u3068let\u3067\u4ee3\u7528\u3067\u304d\u307e\u3059\u3002<\/p>\n

1~10\u307e\u3067\u306e\u5408\u8a08\u3092\u8fd4\u3059<\/h4>\n
const<\/span> fn<\/span> foo<\/span>()<\/span> -><\/span> i32<\/span> {<\/span>\r\n    let<\/span> mut<\/span> i<\/span> =<\/span> 1<\/span>;<\/span>\r\n    let<\/span> mut<\/span> sum<\/span> =<\/span> 0<\/span>;<\/span>\r\n    while<\/span> i<\/span> <=<\/span> 10<\/span> {<\/span>\r\n        sum<\/span> +=<\/span> i<\/span>;<\/span>\r\n        i<\/span> +=<\/span> 1<\/span>;<\/span>\r\n    }<\/span>\r\n    sum<\/span>\r\n}<\/span>\r\n<\/code><\/pre>\n
\u5f15\u6570\u3067\u6e21\u3055\u308c\u305f\u30b9\u30e9\u30a4\u30b9\u306e\u8981\u7d20\u306e\u5408\u8a08\u3092\u8fd4\u3059<\/h4>\n
const<\/span> fn<\/span> sum<\/span>(<\/span>a<\/span>:<\/span> &<\/span>[<\/span>i32<\/span>])<\/span> -><\/span> i32<\/span> {<\/span>\r\n    let<\/span> len<\/span> =<\/span> a<\/span>.len<\/span>();<\/span>\r\n    let<\/span> mut<\/span> i<\/span> =<\/span> 0<\/span>;<\/span>\r\n    let<\/span> mut<\/span> s<\/span> =<\/span> 0<\/span>;<\/span>\r\n    while<\/span> i<\/span> <<\/span> len<\/span> {<\/span>\r\n        s<\/span> +=<\/span> a<\/span>[<\/span>i<\/span>];<\/span>\r\n        i<\/span> +=<\/span> 1<\/span>;<\/span>\r\n    }<\/span>\r\n    s<\/span>\r\n}<\/span>\r\n<\/code><\/pre>\n
abs\u3092\u66f8\u3044\u3066\u307f\u308b<\/h2>\n
\u904e\u53bb\u306babs\u3092\u66f8\u3044\u3066\u3044\u305f\u306e\u30671.46.0\u3067\u3069\u3046\u306a\u3063\u305f\u306e\u304b\u66f8\u304d\u307e\u3059<\/p>\n
const<\/span> fn<\/span> abs<\/span>(<\/span>value<\/span>:<\/span> i32<\/span>)<\/span> -><\/span> i32<\/span> {<\/span>\r\n    if<\/span> value<\/span> >=<\/span> 0<\/span> {<\/span>\r\n        value<\/span>\r\n    }<\/span> else<\/span> {<\/span>\r\n        -<\/span>value<\/span>\r\n    }<\/span>\r\n}<\/span>\r\n<\/code><\/pre>\n
\u666e\u901a\u306e\u95a2\u6570\u3068\u5909\u308f\u3089\u306a\u3044\u3067\u3059\u3002<\/p>\n
\u6240\u611f<\/h2>\n
\u307b\u307c\u666e\u901a\u306e\u95a2\u6570\u3068\u5909\u308f\u3089\u306a\u3044\u66f8\u304d\u65b9\u304c\u3067\u304d\u308b\u3088\u3046\u306b\u306a\u3063\u3066\u304d\u307e\u3057\u305f\u3002
\n\u30b7\u30f3\u30d7\u30eb\u306a\u95a2\u6570\u306a\u3089\u3068\u308a\u3042\u3048\u305aconst\u3064\u3051\u3068\u3044\u3066\u3082\u56f0\u3089\u306a\u3044\u3093\u3058\u3083\u306a\u3044\u3067\u3057\u3087\u3046\u304b\uff1f
\n1.31.0\u30841.39.0\u306e\u3068\u304d\u307f\u305f\u3044\u306a\u82e6\u52b4\u30fb\u5de5\u592b\u3092\u3057\u306a\u304f\u3066\u3044\u3044\u306e\u306f\u3042\u308a\u304c\u305f\u3044\u3067\u3059\u3002<\/p>\n
\u53c2\u8003<\/h2>\n
Announcing Rust 1.46.0
\nRust 1.46\u3092\u65e9\u3081\u306b\u6df1\u6398\u308a – OPTiM TECH BLOG<\/p>\n","protected":false},"excerpt":{"rendered":"
Rust\u306econst fn Rust\u306econst fn\u3067abs Rust\u306econst fn\u306e\u5236\u9650\u304c\u7de9\u548c\u3055\u308c\u305f( […]<\/p>\n","protected":false},"author":5,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-45271","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\/45271-2\/\" \/>\n<meta property=\"og:locale\" content=\"zh_CN\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:description\" content=\"Rust\u306econst fn Rust\u306econst fn\u3067abs Rust\u306econst fn\u306e\u5236\u9650\u304c\u7de9\u548c\u3055\u308c\u305f( […]\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.silicloud.com\/zh\/blog\/45271-2\/\" \/>\n<meta property=\"og:site_name\" content=\"Blog - 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