I am writing a library for WARC support in Perl and some of my tests (and some side features in the library) rely on opening a scalar as a "file", a feature documented as requiring PerlIO, which is default in v5.8 and later, but can be turned off. I also suspect that tied filehandles may require PerlIO.

Searches here at the Monastery turned up a few interesting articles, (Should I list core modules as dependencies?, Re: Should I list core modules as dependencies?, IO::Compress::Gzip and unicode (which answers another question I had), and PerlIO::gzip and Parallel::ForkManager do not play nice) but all seemed to be more about using PerlIO rather than my question of how to express a requirement for PerlIO.

I know that I can test $Config{useperlio} eq 'define' and skip the tests that rely on in-memory files if PerlIO is not in use, but how do I declare this requirement or is there no way to express this in CPAN metadata?

In reply to How to declare a dependency on PerlIO in a CPAN module? by jcb

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