which means there are instantiated loop object in each fetch() running, not a singleton.

That's not right. IO::Async::Loop->new returns a singleton. 

sub new
{
   return our $ONE_TRUE_LOOP ||= shift->really_new;
}

[download]

That shouldn't be a problem, though. If your code is correct, it doesn't matter if multiple modules use the same loop.

In reply to Re^3: IO::Async::Loop in multiple modules all loaded - code provided by ikegami
in thread IO::Async::Loop in multiple modules all loaded by bliako

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