Perl中的单引号和双引号有什么区别?

问题描述

在Perl中，'和"有什么区别?

In Perl, what is the difference between ' and " ?

例如，我有2个变量，如下所示:

For example, I have 2 variables like below:

$var1 = '\(';
$var2 = "\(";

$res1 = ($matchStr =~ m/$var1/);
$res2 = ($matchStr =~ m/$var2/);

$res2语句抱怨Unmatched ( before HERE mark in regex m.

推荐答案

双引号使用变量扩展.单引号不

Double quotes use variable expansion. Single quotes don't

在双引号字符串中，您需要转义某些字符以阻止对它们的不同解释.用单引号引起来的字符串中没有(反斜杠除外，如果它是字符串中的最后一个字符)

In a double quoted string you need to escape certain characters to stop them being interpreted differently. In a single quoted string you don't (except for a backslash if it is the final character in the string)

my $var1 = 'Hello';

my $var2 = "$var1";
my $var3 = '$var1';

print $var2;
print "\n";
print $var3;
print "\n";

这将输出

Hello
$var1

Perl僧侣对此此处

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