{"id":451,"date":"2026-05-05T15:20:15","date_gmt":"2026-05-05T06:20:15","guid":{"rendered":"https:\/\/www.zeronana.net\/?p=451"},"modified":"2026-05-06T15:43:31","modified_gmt":"2026-05-06T06:43:31","slug":"%e3%80%90%e5%ae%9f%e5%8b%99%e5%90%91%e3%81%91%e3%80%91go-defer%e3%81%ae%e4%bd%bf%e3%81%84%e6%96%b9%ef%bd%9c%e5%ae%9f%e8%a1%8c%e3%82%bf%e3%82%a4%e3%83%9f%e3%83%b3%e3%82%b0%e3%81%a8%e5%ae%9f%e8%a3%85","status":"publish","type":"post","link":"https:\/\/www.zeronana.net\/?p=451","title":{"rendered":"\u3010\u5b9f\u52d9\u5411\u3051\u3011Go defer\u306e\u4f7f\u3044\u65b9\uff5c\u5b9f\u884c\u30bf\u30a4\u30df\u30f3\u30b0\u3068\u5b9f\u88c5\u30d1\u30bf\u30fc\u30f3\u3092\u89e3\u8aac"},"content":{"rendered":"\n

Go\u8a00\u8a9e\u3092\u5b66\u3073\u59cb\u3081\u308b\u3068\u5fc5\u305a\u51fa\u3066\u304f\u308b\u306e\u304c\u300cdefer\u300d\u3067\u3059\u3002
\u4e00\u898b\u30b7\u30f3\u30d7\u30eb\u3067\u3059\u304c\u3001\u5b9f\u884c\u30bf\u30a4\u30df\u30f3\u30b0\u3084\u6319\u52d5\u3092\u7406\u89e3\u3057\u3066\u3044\u306a\u3044\u3068\u30d0\u30b0\u306e\u539f\u56e0\u306b\u306a\u308b\u91cd\u8981\u6a5f\u80fd<\/strong>\u3067\u3082\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n

\u672c\u8a18\u4e8b\u3067\u306f\u3001Go\u306edefer\u306b\u3064\u3044\u3066\u300c\u4f7f\u3044\u65b9\u30fb\u30bf\u30a4\u30df\u30f3\u30b0\u30fb\u5b9f\u52d9\u3067\u306e\u6d3b\u7528\u65b9\u6cd5\u300d\u3092\u308f\u304b\u308a\u3084\u3059\u304f\u89e3\u8aac\u3057\u307e\u3059\u3002<\/p>\n\n\n\n

\n\n\n\n

defer\u3068\u306f\uff1f<\/h2>\n\n\n\n

defer\u306f\u3001\u95a2\u6570\u306e\u7d42\u4e86\u6642\u306b\u5b9f\u884c\u3055\u308c\u308b\u51e6\u7406\u3092\u4e88\u7d04\u3059\u308b\u30ad\u30fc\u30ef\u30fc\u30c9<\/strong>\u3067\u3059\u3002<\/p>\n\n\n\n

defer fmt.Println(\"\u7d42\u4e86\u51e6\u7406\")<\/code><\/pre>\n\n\n\n
\u3053\u306e\u30b3\u30fc\u30c9\u306f\u3001\u305d\u306e\u5834\u3067\u306f\u5b9f\u884c\u3055\u308c\u305a\u3001\u95a2\u6570\u304c\u7d42\u308f\u308b\u30bf\u30a4\u30df\u30f3\u30b0\u3067\u5b9f\u884c\u3055\u308c\u307e\u3059\u3002<\/strong><\/p>\n\n\n\n
\n\n\n\n
\u5b9f\u884c\u30bf\u30a4\u30df\u30f3\u30b0\uff08\u3053\u3053\u91cd\u8981\uff09<\/h2>\n\n\n\n
defer\u306f\u4ee5\u4e0b\u306e\u30bf\u30a4\u30df\u30f3\u30b0\u3067\u5b9f\u884c\u3055\u308c\u307e\u3059\ud83d\udc47<\/p>\n\n\n\n
\ud83d\udc49 \u95a2\u6570\u306ereturn\u76f4\u524d<\/strong><\/p>\n\n\n\n
func main() {
    defer fmt.Println(\"defer\")

    fmt.Println(\"start\")
}<\/code><\/pre>\n\n\n\n
\ud83d\udc49 \u51fa\u529b<\/p>\n\n\n\n
start
defer<\/code><\/pre>\n\n\n\n
\u3064\u307e\u308a\ud83d\udc47
\u300c\u51e6\u7406\u306e\u6700\u5f8c\u306b\u5fc5\u305a\u5b9f\u884c\u3055\u308c\u308b\u300d<\/strong><\/p>\n\n\n\n
\n\n\n\n
\u8907\u6570defer\u306e\u6319\u52d5\uff08LIFO\uff09<\/h2>\n\n\n\n
defer\u306f\u8907\u6570\u66f8\u304f\u3068\u3001\u5f8c\u304b\u3089\u66f8\u3044\u305f\u3082\u306e\u304c\u5148\u306b\u5b9f\u884c<\/strong>\u3055\u308c\u307e\u3059\u3002<\/p>\n\n\n\n
defer fmt.Println(\"1\")
defer fmt.Println(\"2\")
defer fmt.Println(\"3\")<\/code><\/pre>\n\n\n\n
\ud83d\udc49 \u51fa\u529b<\/p>\n\n\n\n
3
2
1<\/code><\/pre>\n\n\n\n
\ud83d\udc49 \u30b9\u30bf\u30c3\u30af\u69cb\u9020\uff08LIFO\uff09\u3067\u3059<\/p>\n\n\n\n
\n\n\n\n
\u5b9f\u52d9\u3067\u306e\u4f7f\u3044\u65b9\u2460\uff1a\u30d5\u30a1\u30a4\u30eb\u30af\u30ed\u30fc\u30ba<\/h2>\n\n\n\n
file, err := os.Open(\"test.txt\")
if err != nil {
    return err
}
defer file.Close()<\/code><\/pre>\n\n\n\n
\ud83d\udc49 \u30dd\u30a4\u30f3\u30c8<\/p>\n\n\n\n
    \n
  • \u958b\u3044\u305f\u3089\u3059\u3050defer<\/li>\n\n\n\n
  • \u66f8\u304d\u5fd8\u308c\u9632\u6b62<\/li>\n<\/ul>\n\n\n\n
    \n\n\n\n
    \u5b9f\u52d9\u3067\u306e\u4f7f\u3044\u65b9\u2461\uff1aDB\u63a5\u7d9a\u306e\u30af\u30ed\u30fc\u30ba<\/h2>\n\n\n\n
    db, err := sql.Open(\"mysql\", dsn)
    if err != nil {
        return err
    }
    defer db.Close()<\/code><\/pre>\n\n\n\n
    \ud83d\udc49 \u63a5\u7d9a\u30ea\u30bd\u30fc\u30b9\u306e\u89e3\u653e\u306f\u5fc5\u9808
    \ud83d\udc49 defer\u3067\u5b89\u5168\u306b\u7ba1\u7406<\/p>\n\n\n\n
    \n\n\n\n
    \u5b9f\u52d9\u3067\u306e\u4f7f\u3044\u65b9\u2462\uff1a\u30ed\u30c3\u30af\u89e3\u9664<\/h2>\n\n\n\n
    mu.Lock()
    defer mu.Unlock()<\/code><\/pre>\n\n\n\n
    \ud83d\udc49 \u30a8\u30e9\u30fc\u304c\u8d77\u304d\u3066\u3082\u5fc5\u305aUnlock\u3055\u308c\u308b
    \ud83d\udc49 \u4e26\u884c\u51e6\u7406\u3067\u306f\u8d85\u91cd\u8981<\/p>\n\n\n\n
    \n\n\n\n
    \u3088\u304f\u3042\u308b\u30df\u30b9\uff08\u91cd\u8981\uff09<\/h2>\n\n\n\n
    \u274c defer\u306f\u3059\u3050\u8a55\u4fa1\u3055\u308c\u308b<\/h3>\n\n\n\n
    defer fmt.Println(x)
    x = 10<\/code><\/pre>\n\n\n\n
    \ud83d\udc49 \u51fa\u529b\u306f\u300c\u5143\u306ex\u300d<\/p>\n\n\n\n
    \ud83d\udc49 \u7406\u7531<\/p>\n\n\n\n
      \n
    • \u5f15\u6570\u306fdefer\u6642\u70b9\u3067\u8a55\u4fa1\u3055\u308c\u308b<\/strong><\/li>\n<\/ul>\n\n\n\n
      \n\n\n\n
      \u274c \u30eb\u30fc\u30d7\u5185defer\u306e\u6ce8\u610f<\/h3>\n\n\n\n
      for i := 0; i < 5; i++ {
          defer fmt.Println(i)
      }<\/code><\/pre>\n\n\n\n
      \ud83d\udc49 \u5168\u90e8\u307e\u3068\u3081\u3066\u6700\u5f8c\u306b\u5b9f\u884c\u3055\u308c\u308b
      \ud83d\udc49 \u30e1\u30e2\u30ea\u5727\u8feb\u306e\u539f\u56e0\u306b\u306a\u308b\u3053\u3068\u3082<\/p>\n\n\n\n
      \n\n\n\n
      \u5b9f\u52d9\u3067\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/h2>\n\n\n\n
      \u2714 \u30ea\u30bd\u30fc\u30b9\u958b\u653e\u306f\u5fc5\u305adefer
      \u2714 \u95a2\u6570\u306e\u65e9\u3044\u6bb5\u968e\u3067\u66f8\u304f
      \u2714 \u30eb\u30fc\u30d7\u5185\u3067\u591a\u7528\u3057\u306a\u3044
      \u2714 error\u51e6\u7406\u3068\u7d44\u307f\u5408\u308f\u305b\u308b<\/p>\n\n\n\n
      \n\n\n\n
      \u30a8\u30e9\u30fc\u30cf\u30f3\u30c9\u30ea\u30f3\u30b0\u3068\u306e\u7d44\u307f\u5408\u308f\u305b<\/h2>\n\n\n\n
      Go\u3067\u306fdefer\u3068error\u51e6\u7406\u3092\u7d44\u307f\u5408\u308f\u305b\u308b\u306e\u304c\u57fa\u672c\u3067\u3059\u3002<\/p>\n\n\n\n
      func readFile() error {
          file, err := os.Open(\"test.txt\")
          if err != nil {
              return err
          }
          defer file.Close()

          \/\/ \u51e6\u7406
          return nil
      }<\/code><\/pre>\n\n\n\n
      \ud83d\udc49
      \u300c\u30a8\u30e9\u30fc\u51e6\u7406 \u00d7 defer\u300d\uff1d\u5b9f\u52d9\u306e\u57fa\u672c\u30d1\u30bf\u30fc\u30f3<\/strong><\/p>\n\n\n\n
      \n\n\n\n
      \u307e\u3068\u3081<\/h2>\n\n\n\n
      Go\u306edefer\u306f\u3001\u30b7\u30f3\u30d7\u30eb\u3067\u3059\u304c\u975e\u5e38\u306b\u5f37\u529b\u306a\u6a5f\u80fd\u3067\u3059\u3002<\/p>\n\n\n\n
      \u30dd\u30a4\u30f3\u30c8\u306f\ud83d\udc47<\/p>\n\n\n\n
        \n
      • \u95a2\u6570\u7d42\u4e86\u6642\u306b\u5b9f\u884c\u3055\u308c\u308b<\/li>\n\n\n\n
      • LIFO\u3067\u51e6\u7406\u3055\u308c\u308b<\/li>\n\n\n\n
      • \u30ea\u30bd\u30fc\u30b9\u7ba1\u7406\u306b\u5fc5\u9808<\/li>\n\n\n\n
      • error\u51e6\u7406\u3068\u7d44\u307f\u5408\u308f\u305b\u308b<\/li>\n<\/ul>\n\n\n\n
        \n\n\n\n
        \ud83d\udca1 \u3053\u306e\u8a18\u4e8b\u306e\u7d50\u8ad6<\/h2>\n\n\n\n
        \ud83d\udc49
        \u300c\u30ea\u30bd\u30fc\u30b9\u3092\u958b\u3044\u305f\u3089\u3059\u3050defer\u3067\u9589\u3058\u308b\u300d<\/strong><\/p>\n\n\n\n
        \u3053\u308c\u3092\u5fb9\u5e95\u3059\u308b\u3060\u3051\u3067\u3001\u30b3\u30fc\u30c9\u54c1\u8cea\u304c\u4e00\u6c17\u306b\u4e0a\u304c\u308a\u307e\u3059\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
        Go\u8a00\u8a9e\u3092\u5b66\u3073\u59cb\u3081\u308b\u3068\u5fc5\u305a\u51fa\u3066\u304f\u308b\u306e\u304c\u300cdefer\u300d\u3067\u3059\u3002\u4e00\u898b\u30b7\u30f3\u30d7\u30eb\u3067\u3059\u304c\u3001\u5b9f\u884c\u30bf\u30a4\u30df\u30f3\u30b0\u3084\u6319\u52d5\u3092\u7406\u89e3\u3057\u3066\u3044\u306a\u3044\u3068\u30d0\u30b0\u306e\u539f\u56e0\u306b\u306a\u308b\u91cd\u8981\u6a5f\u80fd […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"advanced_seo_description":"","jetpack_seo_html_title":"","jetpack_seo_noindex":false,"jetpack_seo_schema_type":"","_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[4],"tags":[6,7],"class_list":["post-451","post","type-post","status-publish","format-standard","hentry","category-go","tag-go-2","tag-go"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/www.zeronana.net\/index.php?rest_route=\/wp\/v2\/posts\/451","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.zeronana.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.zeronana.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.zeronana.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.zeronana.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=451"}],"version-history":[{"count":1,"href":"https:\/\/www.zeronana.net\/index.php?rest_route=\/wp\/v2\/posts\/451\/revisions"}],"predecessor-version":[{"id":452,"href":"https:\/\/www.zeronana.net\/index.php?rest_route=\/wp\/v2\/posts\/451\/revisions\/452"}],"wp:attachment":[{"href":"https:\/\/www.zeronana.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=451"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.zeronana.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=451"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.zeronana.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=451"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}