sockjs/sockjs-erlang — pull request #52 by mikebeam (2013-10-02 13:23:43+00:00)
Title: Add module() as a union type of callback()

According to to sockjs_session:emit/2, the callback can be a module name, which is how our code uses sockjs_handler:init_state/4. The definition of the callback() type as only a fun results in a number of dialyzer warnings, which are resolved by this change.