Suppose you want to grab a different version of just one function. Say, you've updated code and now want to call a newer thing, but have not updated the entire file yet.

use Module v1.0 qw/foo bar/;
use Module v2.0 qw/baz/;  # was not present in 1.0
[download]

That looks easy enough, and should work just fine. But, recall the handling of direct module calls, as opposed to calling through the imported hard link. If you write Module::foo it will decide at run-time that it must mean foo v1.0 based on the caller.

So, what happens if you call Module::zippo, something that was not directly imported also? Should that assume v1.0 or v2.0?

Musings:

• make it illegal - goes against the concept of being able to "maintain" the client and adopt newer features as needed.
• use the first - makes sence from the perspective of not changing what already worked in the client.
• use the last - makes sence from the perspective that the last assignment to a variable (or change to a setting) is the one you see.

However, I'd prefer to avoid the problem and not have the issue come up. E.g. some way to spot-import by version without making the user wonder what happens to the caller's "in use" setting.

For example, use a general syntax for renaming the import and specifying which version you want, and not re-specify a indirect version argument:

use Module v1.0 qw/foo bar/;
use Module --rename => [\&baz, 'baz', v2.0];
[download]

Any ideas?

—John

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