XPND file extensions. What are they?

There's been a problem which has been troubling me recently. I've discovered some files using the extension .xpnd while looking through some Perl examples. Their contents were mostly plain HTML, with the following exception:

[% INCLUDE path_to_random_file.xpnd %]

Could somebody enlighten me on 开发者_StackOverflow中文版the nature of these files and of that tag?

Thanks in advance!

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I'm not familiar with the .xpnd file extension. However, the [% INCLUDE .. %] directive is part of the Template Toolkit (see http://www.template-toolkit.org/) and is used to include templates within templates. I suspect that the .xpnd files are templates local to that particular system and may represent HTML (or whatever) that has been "expanded" by some other part of the system for inclusion in higher level templates. Just a guess.