什么是 @.在Perl？

发布时间：2020-12-15 22:03:22 所属栏目：大数据来源：网络整理

导读：是什么 @. perl中的变量？它看起来是一个特殊的,可写的全局,并且(令人惊讶地)不会在双引号字符串中进行插值： use strict;use warnings; # Under 5.8,5.10,5.12,5.14,and 5.16,# the following lines produce:@. = (3,2,1); # no errorprint "@.n"; # "@."

是什么 @. perl中的变量？

它看起来是一个特殊的,可写的全局,并且(令人惊讶地)不会在双引号字符串中进行插值：

use strict;
use warnings;

                 # Under 5.8,5.10,5.12,5.14,and 5.16,# the following lines produce:

@. = (3,2,1);  # no error
print "@.n";    # "@."
print @.,"n";  # "321"

eval 'my @.; 1'  # Can't use global @. in "my" at (eval 1)
  or die $@;     #  line 1,near "my @."

我记不起曾经遇到它,并没有在perlvar和perldata中看到它.

解决方法

perldoc perlvar州：

Perl variable names may also be a sequence of digits or a single punctuation or control character. These names are all reserved for special uses by Perl;

和

Perl identifiers that begin with digits,control characters,or punctuation characters are exempt from the effects of the package declaration and are always forced to be in package main; they are also exempt from strict 'vars' errors.

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（编辑：李大同）

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