map, grepのブロックの中でreturnするとそのブロックではなくその外側のブロック(サブルーチンなど)からreturnする。 perl v5.14.2で確認。 use strict; use warnings; use feature qw(say); use List::Util qw(first reduce); sub custom1(&) { shift->(); } sub custom2(&@) { shift->(); } sub test_grep { my @a = (1); @a = grep { return 'from inside grep' } @a; return 'from outside grep'; } sub test_map { my @a = (1); @a = map { return 'from inside map' } @a; re
![map, grepの中でreturn - Qiita](https://cdn-ak-scissors.b.st-hatena.com/image/square/808838db6767ac695e044df39187f81b02ba5572/height=288;version=1;width=512/https%3A%2F%2Fqiita-user-contents.imgix.net%2Fhttps%253A%252F%252Fcdn.qiita.com%252Fassets%252Fpublic%252Farticle-ogp-background-9f5428127621718a910c8b63951390ad.png%3Fixlib%3Drb-4.0.0%26w%3D1200%26mark64%3DaHR0cHM6Ly9xaWl0YS11c2VyLWNvbnRlbnRzLmltZ2l4Lm5ldC9-dGV4dD9peGxpYj1yYi00LjAuMCZ3PTkxNiZoPTMzNiZ0eHQ9bWFwJTJDJTIwZ3JlcCVFMyU4MSVBRSVFNCVCOCVBRCVFMyU4MSVBN3JldHVybiZ0eHQtY29sb3I9JTIzMjEyMTIxJnR4dC1mb250PUhpcmFnaW5vJTIwU2FucyUyMFc2JnR4dC1zaXplPTU2JnR4dC1jbGlwPWVsbGlwc2lzJnR4dC1hbGlnbj1sZWZ0JTJDdG9wJnM9OGJlZGNlNzQ2MDEyY2Y1YjU5MzkyNWM2N2ZkY2Y3Nzk%26mark-x%3D142%26mark-y%3D112%26blend64%3DaHR0cHM6Ly9xaWl0YS11c2VyLWNvbnRlbnRzLmltZ2l4Lm5ldC9-dGV4dD9peGxpYj1yYi00LjAuMCZ3PTcxNiZ0eHQ9JTQwZGVidWctaXRvJnR4dC1jb2xvcj0lMjMyMTIxMjEmdHh0LWZvbnQ9SGlyYWdpbm8lMjBTYW5zJTIwVzYmdHh0LXNpemU9MzImdHh0LWFsaWduPWxlZnQlMkN0b3Amcz01MGJhMGE4OGZlZDlkZGQ1NzdlMjdhZWMyMWNlMzY4NA%26blend-x%3D142%26blend-y%3D491%26blend-mode%3Dnormal%26s%3D81e0924e7f0f43bacb324b3185d9e4a6)