I'm assuming that Net::Server::POP3 inherits from some basic Net::Server module that provides basic server functionality. Even if it doesn't, let's say that it does.

Now, let's say that there is some other server base module, called Net2::Server. It provides a very similar (but not identical) interface, but radically different innards. It's useful for different types of servers.

Now, let's say that I am using five servers, each an object of a class that either inherits from Net::Server or Net2::Server. I don't know which inherits from which. But, I do know that there is one interface difference I need to be aware of - foo() vs. bar(). So, I can do the following: 

my $method = $server->can('foo') || $server->can('bar');
$server->$method( @args );

[download]

And I guarantee that my code will work, regardless of which baseclass the server inherits from.

------
We are the carpenters and bricklayers of the Information Age.

Then there are Damian modules.... *sigh* ... that's not about being less-lazy -- that's about being on some really good drugs -- you know, there is no spoon. - flyingmoose

In reply to Re: What is this can() and why is breaking it (un)acceptable? by dragonchild
in thread Why breaking can() is acceptable by tilly

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