perl - 如何在 Perl 中进行非插值字符串插值

Question

一旦确定下面的字符串中包含“$”，我该如何对其进行插值？

use strict;

my $yrs;
my $stg = 'He is $yrs years old.';

if ($stg =~ /[@#\$\%\/]/) {

    print "Matched dollar sign.\n";
    $yrs = '4';
    
} else {

    print "No Match.\n";

}

print "Year's scalar: $yrs\n";
print $stg . "\n";

我明白了:

He is $yrs years old.

我想得到:

He is 4 years old.

Answer 1

您正在尝试编写模板系统。周围有很多，因此您不必费心编写自己的代码。

use Template qw( );

my $template = 'He is [% years %] years old.';

my $vars = {
   years => 4,
};

my $tt = Template->new();
$tt->process(\$template, $vars, \my $output)
   or die($tt->error());

say $output;