In Net::IMAP and others, a module will pass you data by requiring that you pass a subroutine reference that the module will execute when the time comes to pass back the data.

Then I have to use uncomfortable globals to get the data out of that sub and it's harder to debug because I don't know what's calling my sub and what my sub returns.

Am I missing the beauty of callbacks? What are they for? Why would someone use them instead of just returning a hash ref or something like that?

In reply to Why callbacks? by pileofrogs

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