reverse 不在列表上下文中隐式使用 $_，这是一个错误吗? [英] reverse doesn't use $_ implicitly in list context, is this a bug?

问题描述

@array = reverse;和@array = 反向 $_;

两者都不一样.@array = reverse 不隐式使用 $_.我们必须显式声明 $_.这是一个非常奇怪的情况，默认情况下没有使用 $_.是bug吗?

解决方案

据我了解 反向文档，反向适用于数组，所以它应该使用@_而不是标量$_?

文档说在标量上下文中不带参数使用，reverse()反转$_."[强调]

$_ = "dlrow ,olleH";反印；# 无输出，列出上下文打印标量反转；# 你好，世界

@array = reverse; 
and 
@array = reverse $_;

Both are different. @array = reverse doesn't use $_ implicitly. We have to declare $_ explicitly. It's a very strange case where $_ is not being used by default. Is it a bug?

解决方案

As far as I understand from the reverse documentation, reverse works on arrays, and so it should use @_ rather than the scalar $_?

The documentation says "Used without arguments in scalar context, reverse() reverses $_." [Emphasis added]

$_ = "dlrow ,olleH";
print reverse;                              # No output, list context
print scalar reverse;                       # Hello, world

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