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Re: Trying to Understand Callback(s)

by ikegami (Patriarch)
on Nov 23, 2017 at 22:53 UTC ( [id://1204174] : note . print w/replies, xml ) Need Help??


in reply to Trying to Understand Callback(s)

\&get_callback doesn't call get_callback; it returns a reference to it. This reference will be used by get to invoke the sub at a later time (e.g. when the request succeeds or fails). When get invokes it, it will pass parameters to it.

sub get { my ($ua, $url, $cb) = @_; ... $cb->($foo, $tx); # Call the referenced sub. ... }