{"id":453,"date":"2026-05-05T21:06:47","date_gmt":"2026-05-05T12:06:47","guid":{"rendered":"https:\/\/www.zeronana.net\/?p=453"},"modified":"2026-05-06T15:43:25","modified_gmt":"2026-05-06T06:43:25","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%85-2","status":"publish","type":"post","link":"https:\/\/www.zeronana.net\/?p=453","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"},"content":{"rendered":"\n

Go\u8a00\u8a9e\u306edefer<\/code>\u306f\u3001\u95a2\u6570\u7d42\u4e86\u6642\u306b\u51e6\u7406\u3092\u5b9f\u884c\u3059\u308b\u305f\u3081\u306e\u91cd\u8981\u6a5f\u80fd<\/strong>\u3067\u3059\u3002
\u30ea\u30bd\u30fc\u30b9\u7ba1\u7406\u3084\u30a8\u30e9\u30fc\u30cf\u30f3\u30c9\u30ea\u30f3\u30b0\u3068\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u3001\u5b89\u5168\u3067\u4fdd\u5b88\u6027\u306e\u9ad8\u3044\u30b3\u30fc\u30c9<\/strong>\u304c\u66f8\u3051\u307e\u3059\u3002<\/p>\n\n\n\n

\u672c\u8a18\u4e8b\u3067\u306f\u3001defer\u306e\u300c\u4f7f\u3044\u65b9\u30fb\u30bf\u30a4\u30df\u30f3\u30b0\u30fb\u5b9f\u88c5\u300d\u3092\u5b9f\u52d9\u8996\u70b9\u3067\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<\/code>\u306f\u3001\u5f8c\u3067\u5b9f\u884c\u3057\u305f\u3044\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
\ud83d\udc49 \u3053\u306e\u51e6\u7406\u306f\u5373\u5b9f\u884c\u3055\u308c\u305a\u3001
\ud83d\udc49 \u95a2\u6570\u304c\u7d42\u4e86\u3059\u308b\u76f4\u524d\u306b\u5b9f\u884c\u3055\u308c\u307e\u3059<\/strong><\/p>\n\n\n\n
\n\n\n\n
\u5b9f\u884c\u30bf\u30a4\u30df\u30f3\u30b0\uff08\u91cd\u8981\uff09<\/h2>\n\n\n\n
defer\u306f\u5fc5\u305a\ud83d\udc47\u306e\u30bf\u30a4\u30df\u30f3\u30b0\u3067\u52d5\u304d\u307e\u3059<\/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
\u51fa\u529b<\/h3>\n\n\n\n
start
defer<\/code><\/pre>\n\n\n\n
\n\n\n\n
\u8907\u6570defer\u306e\u6319\u52d5\uff08LIFO\uff09<\/h2>\n\n\n\n
\u8907\u6570\u66f8\u3044\u305f\u5834\u5408\ud83d\udc47<\/p>\n\n\n\n
defer fmt.Println(\"1\")
defer fmt.Println(\"2\")
defer fmt.Println(\"3\")<\/code><\/pre>\n\n\n\n
\u51fa\u529b<\/h3>\n\n\n\n
3
2
1<\/code><\/pre>\n\n\n\n
\ud83d\udc49 \u5f8c\u304b\u3089\u66f8\u3044\u305f\u3082\u306e\u304c\u5148\u306b\u5b9f\u884c\uff08\u30b9\u30bf\u30c3\u30af\u69cb\u9020\uff09<\/strong><\/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 \u958b\u3044\u305f\u76f4\u5f8c\u306b\u66f8\u304f\u306e\u304c\u9244\u5247
\ud83d\udc49 \u66f8\u304d\u5fd8\u308c\u9632\u6b62<\/p>\n\n\n\n
\n\n\n\n
\u5b9f\u52d9\u3067\u306e\u4f7f\u3044\u65b9\u2461\uff1aDB\u63a5\u7d9a<\/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 \u30ea\u30bd\u30fc\u30b9\u89e3\u653e\u306f\u5fc5\u9808
\ud83d\udc49 defer\u3067\u5b89\u5168\u306b\u51e6\u7406<\/p>\n\n\n\n
\n\n\n\n
\u5b9f\u52d9\u3067\u306e\u4f7f\u3044\u65b9\u2462\uff1a\u30ed\u30c3\u30af\u5236\u5fa1<\/h2>\n\n\n\n
mu.Lock()
defer mu.Unlock()<\/code><\/pre>\n\n\n\n
\ud83d\udc49 \u30a8\u30e9\u30fc\u767a\u751f\u6642\u3082\u5fc5\u305aUnlock\u3055\u308c\u308b
\ud83d\udc49 \u4e26\u884c\u51e6\u7406\u3067\u306f\u5fc5\u9808\u30c6\u30af\u30cb\u30c3\u30af<\/p>\n\n\n\n
\n\n\n\n
\u3088\u304f\u3042\u308b\u30df\u30b9<\/h2>\n\n\n\n
\u274c \u5f15\u6570\u306fdefer\u6642\u306b\u8a55\u4fa1\u3055\u308c\u308b<\/h3>\n\n\n\n
x := 1
defer fmt.Println(x)
x = 10<\/code><\/pre>\n\n\n\n
\ud83d\udc49 \u51fa\u529b\u306f\u300c1\u300d<\/p>\n\n\n\n
\n\n\n\n
\u274c \u30eb\u30fc\u30d7\u5185defer\u306f\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 \u6700\u5f8c\u306b\u307e\u3068\u3081\u3066\u5b9f\u884c
\ud83d\udc49 \u30e1\u30e2\u30ea\u6d88\u8cbb\u5897\u306e\u539f\u56e0\u306b\u306a\u308b\u3053\u3068\u3082<\/p>\n\n\n\n
\n\n\n\n
\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/h2>\n\n\n\n
    \n
  • \u30ea\u30bd\u30fc\u30b9\u958b\u653e\u306f\u5fc5\u305adefer<\/li>\n\n\n\n
  • \u53d6\u5f97\u76f4\u5f8c\u306b\u66f8\u304f<\/li>\n\n\n\n
  • \u30eb\u30fc\u30d7\u5185\u3067\u591a\u7528\u3057\u306a\u3044<\/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
    \u30a8\u30e9\u30fc\u30cf\u30f3\u30c9\u30ea\u30f3\u30b0\u3068\u306e\u7d44\u307f\u5408\u308f\u305b<\/h2>\n\n\n\n
    func readFile() error {
        file, err := os.Open(\"test.txt\")
        if err != nil {
            return err
        }
        defer file.Close()

        return nil
    }<\/code><\/pre>\n\n\n\n
    \ud83d\udc49
    defer \u00d7 error\u51e6\u7406\uff1dGo\u5b9f\u52d9\u306e\u57fa\u672c<\/strong><\/p>\n\n\n\n
    \n\n\n\n
    \u307e\u3068\u3081<\/h2>\n\n\n\n
    Go\u306edefer\u306f\ud83d\udc47\u304c\u3059\u3079\u3066\u3067\u3059<\/p>\n\n\n\n
      \n
    • \u95a2\u6570\u7d42\u4e86\u6642\u306b\u5b9f\u884c<\/li>\n\n\n\n
    • LIFO\uff08\u5f8c\u5165\u308c\u5148\u51fa\u3057\uff09<\/li>\n\n\n\n
    • \u30ea\u30bd\u30fc\u30b9\u7ba1\u7406\u306b\u6700\u9069<\/li>\n\n\n\n
    • error\u51e6\u7406\u3068\u30bb\u30c3\u30c8\u3067\u4f7f\u3046<\/li>\n<\/ul>\n\n\n\n
      \n\n\n\n
      \ud83d\udca1 \u7d50\u8ad6<\/h2>\n\n\n\n
      \ud83d\udc49
      \u300c\u958b\u3044\u305f\u3089\u3059\u3050defer\u3067\u9589\u3058\u308b\u300d<\/strong><\/p>\n\n\n\n
      \u3053\u308c\u3092\u5fb9\u5e95\u3059\u308c\u3070\u3001
      \u30d0\u30b0\u304c\u6e1b\u308a\u3001\u54c1\u8cea\u306e\u9ad8\u3044\u30b3\u30fc\u30c9\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
      Go\u8a00\u8a9e\u306edefer\u306f\u3001\u95a2\u6570\u7d42\u4e86\u6642\u306b\u51e6\u7406\u3092\u5b9f\u884c\u3059\u308b\u305f\u3081\u306e\u91cd\u8981\u6a5f\u80fd\u3067\u3059\u3002\u30ea\u30bd\u30fc\u30b9\u7ba1\u7406\u3084\u30a8\u30e9\u30fc\u30cf\u30f3\u30c9\u30ea\u30f3\u30b0\u3068\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u3001\u5b89\u5168\u3067\u4fdd\u5b88\u6027\u306e\u9ad8 […]<\/p>\n","protected":false},"author":1,"featured_media":454,"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-453","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-go","tag-go-2","tag-go"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"https:\/\/www.zeronana.net\/wp-content\/uploads\/2026\/05\/neo.png","_links":{"self":[{"href":"https:\/\/www.zeronana.net\/index.php?rest_route=\/wp\/v2\/posts\/453","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=453"}],"version-history":[{"count":1,"href":"https:\/\/www.zeronana.net\/index.php?rest_route=\/wp\/v2\/posts\/453\/revisions"}],"predecessor-version":[{"id":455,"href":"https:\/\/www.zeronana.net\/index.php?rest_route=\/wp\/v2\/posts\/453\/revisions\/455"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.zeronana.net\/index.php?rest_route=\/wp\/v2\/media\/454"}],"wp:attachment":[{"href":"https:\/\/www.zeronana.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=453"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.zeronana.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=453"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.zeronana.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=453"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}