Does not include the enhanced top-level, which will be added in a later update.
From Christopher Zimmermann <madroach@gmerlin.de>
--
Lwt provides very light-weight cooperative threads for OCaml;
``launching'' a thread is a very fast operation, it does not require
a new stack, a new process, or anything else. Moreover context
switches are very fast. In fact, it is so easy that a thread can
be launched for every system call. And composing cooperative threads
will allow highly asynchronous programs.
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