bug#14270: shadow.el, simple.el, shadows shadows

[Greg Minshall <minshall@umich.edu>]

hi.  in shadow.el, list-load-path-shadows has some code to look for the
(originally, first; now last)
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http://lists.gnu.org/archive/html/bug-gnu-emacs/2002-03/msg00507.html
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directory with simple.el in it.  i *assume* that originally, there were
no directories underneath, e.g., /usr/local/share/emacs/24.3/lisp.  but
now, subsystems seem to live in directories.  i.e., in my case, the
following are subdirectories:
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calc calendar cedet emacs-lisp emulation erc eshell gnus international
language mail mh-e net nxml obsolete org play progmodes term textmodes
url vc
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in my setup, i have local copies of mh-e and org.  if i say M-x
list-load-path-shadows, i get the message that
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No Emacs Lisp load-path shadowings were found
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but, if i disable the search for simple.el, i instead get the more
accurate:
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118 Emacs Lisp load-path shadowings were found
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i wonder if the test for simple.el might be removed?  it appears that it
was designed to help in the case where a developer's own load-path
includes his/her source directory (and, with the above change from first
to last, i'm not sure if it even fulfills that desire).  if there's
still a desire for that behavior, maybe a customizable list of
directories to ignore, similar to (but markedly different from) the
suggestion in
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http://lists.gnu.org/archive/html/bug-gnu-emacs/2012-09/msg00135.html
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cheers, Greg Minshall