() Eli Zaretskii <eliz@gnu.org>
() Tue, 14 Apr 2015 05:38:09 +0300

   Likely a buffering issue.  Emacs on Windows runs subprocesses
   via a pipe, and many programs then buffer their stdout fully,
   unlike line buffering they use when run from a shell prompt.

   If "lein repl", whatever that is, has an option to control
   buffering, or there's a variable you can set or command you
   can issue to that effect inside "lein repl", they will likely
   fix the problem.

Another possible weirdness is EOL convention.  But anyway...

You found a solution in ‘cider-jack-in’.  Why don't you examine
its source code, examine the ‘M-x shell’ source code and post
the conceptual diff?  (If not you, then Someone ought to do it.)

source but no reading of it: we are blind.
reading of source but no understanding: we are dumb.
understanding of one but not of many: we are alone.
how funny the universe allows us to say "we" are "alone".  :-D

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