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in reply to Re: How can I (safely) use packages of the same name but different versions?
in thread How can I (safely) use packages of the same name but different versions?

I don't know anything about xevian's situation, but one place where I can see something kind of like this come up is when there are backward compatibility problems. For example, let's say DBD::XYZ version 1 only supports XYZ database version 1, whereas DBD::XYZ version 2 only supports XYZ database version 2. If your code, for whatever reason, might have to connect to instances of different versions of XYZ within a single program, you're going to have a problem.

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Re^3: How can I (safely) use packages of the same name but different versions?
by samtregar (Abbot) on Mar 12, 2008 at 16:08 UTC
    I've heard rumors that Perl 6 will solve this problem. Personally I don't think it's going to be all that helpful. New versions are released for a reason - leaving old code using old versions of their dependencies is only going to get you so far. Your example is a good one - if XYZ v1 and v2 are both being used to access the same physical database then you've likely got a problem that Perl alone supporting multiple version loading can't solve.

    I haven't had a chance to try it yet, but I thought Erlang's facility for running multiple versions of code long enough to do a seemless cut-over sounded smart. Since everything in Erlang is a networked server the system starts up the new version and starts sending all new requests to it. Once the old version is done handling any lingering requests it gets shutdown.

    -sam

[reply]
      The database thing happens to be a non-hypothetical question for me. I'm not giving details because my actual situation involves Java, not Perl, but the concept is the same.
[reply]

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