$_ 的奇怪值/行为 [英] Strange values/behavior of $_

问题描述

输出应该是aaabbbcccdddeee，而不是aaa555234dddeee

perl -wle'
    map { for (my $i =2; $i <5; $i++) { push @a, $_ } } "a".."e";
    print @a
'
aaa555234dddeee

仅在引用/取消引用 $_ 变量时的预期行为，

expected behavior only when referencing/dereferencing $_ variable,

perl -wle'
    map { for (my $i =2; $i <5; $i++) { push @a, ${\$_} } } "a".."e";
    print @a
'
aaabbbcccdddeee

这是记录在案的错误(或功能)吗?

Is this a documented bug (or feature)?

推荐答案

在我看来，这是上个月报告的错误的一个实例(但已经存在 12 年了):https://rt.perl.org/Public/Bug/Display.html?id=123285

Looks to me like this is an instance of a bug reported just last month (but that has been around for 12 years): https://rt.perl.org/Public/Bug/Display.html?id=123285

它已修复，但我不相信任何已发布的版本.

It is fixed but I don't believe in any released version yet.

这篇关于$_ 的奇怪值/行为的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！