On 2021-02-18, Karl Berry <karl@xxxxxxxxxxxxxxx> wrote: > I think the right thresholds are 5.10 for absolute minimum and 5.16 > for 'we aren't going to test with anything older than this' > > I appreciate the effort to increase compatibility with old versions. > > I imagine you could provide Digest::SHA "internally", or test for it as > Nick suggested, but I know how much of a pain it is to avoid/check for > use of things that have seemingly been around forever. (Comes up all the > time in the TeX world.) Just to clarify, I was not suggesting that any kind of test is needed before going ahead and using this module. If there is a good reason to use the module in Autoconf, as far as I'm concerned we should just go ahead and use it. I was just pointing out that requiring this module in Autoconf does not, by itself, imply requiring perl 5.10, as the module may be available on older installations too. The reason for failures due to a missing module like this will be obvious immediately. A configure test may be _nice_ but probably just extra work that is not really needed. Cheers, Nick