我如何安全地为Perl 5.8.9编译Perl 5.12模块？

我想在Perl 5.8.9中安装File :: Fetch，这是Perl 5.12中的核心模块。一般来说，我想编译和安装未来的模块在我的回溯的Perl因为我不能升级我的Perl。

I want to install File::Fetch, which is a core module in Perl 5.12, in my Perl 5.8.9. In general, I want to compile and install future-dated modules in my back-dated Perl because I cannot upgrade my Perl.

所以我下载了模块及其依赖项。这是相当痛苦的依赖树后，但我更关心的事实，其中一些是核心模块。如果我安装这些，我的Perl 5.8.9核心将有5.12的补丁。

So I downloaded the module and also its dependencies. It's quite painful following the dependency tree but I'm more concerned about the fact that some of them are core modules. If I install these, my Perl 5.8.9 core will have patches from 5.12.

我的问题是如何知道我是否可以安全地安装未来的模块，特别是核心模块。是否有一个教程用于测试Perl中的向后兼容性？

My question is how I can know whether I can safely install the future-dated modules, especially the core modules. Is there a tutorial for this purpose of testing backwardcompatability in Perl?

编辑：

我的模块是双重的，但是我不能使用cpan 。它说我的FTPsite.yaml有一个坏的元素。但是，我遵循模块的META文件中的依赖关系，我可以编译模块。这是cpan的奇数位吗？谢谢。

My module is dual lifed, but I cannot compile it using cpan. It said my FTPsite.yaml has a bad element. However, I followed the dependencies in the modules' META files, and I could compiled the module. Is this one of the odd bits with cpan? Thank you.

我手动安装所有依赖项后无法重新创建问题。但这里是错误：

I cannot recreate the issue after I installed all those dependencies manually. But here is the error:

cpan[5]> install File::Fetch
Running install for module 'File::Fetch'
Running make for B/BI/BINGOS/File-Fetch-0.24.tar.gz
CPAN: Digest::SHA loaded ok (v5.48)
CPAN: Time::HiRes loaded ok (v1.9715)
CPAN: YAML loaded ok (v0.72)
Alert: While trying to 'parse' YAML file
 '/Users/martin/.cpan/FTPstats.yml'
with 'YAML' the following error was encountered:
  YAML Error: Invalid element in map
   Code: YAML_LOAD_ERR_BAD_MAP_ELEMENT
   Line: 3
   Document: 1
 at /opt/local/lib/perl5/site_perl/5.8.9/YAML.pm line 36