regex - Perl 正则表达式 : Does the at sign @ need to be escaped?

Question

我无法确定我的正则表达式失败的原因。这是我的代码:

my $email = "rise@dawn.com";
my ($found) = $email =~ /(rise@dawn\.com)/;
print "Found: $found";

这导致输出:

C:\scripts\perl\sandbox>regex.pl
Found: rise.com

如果我转义 @ 符号，则根本没有输出:

my $email = "rise@dawn.com";
my ($found) = $email =~ /(rise\@dawn\.com)/;
print "Found: $found";

C:\scripts\perl\sandbox>regex.pl
Found:

有人可以请教我我的错误。

Answer 1

永远 use strict; use warnings;在脚本的顶部!

它会警告你有一个未声明的全局变量 @dawn .数组也可以插入双引号字符串，所以你需要

my $email = "rise\@dawn.com";
my ($found) = $email =~ /(rise\@dawn\.com)/;
print "Found: $found";