Better documentation of 'emacs-internal' encoding

* doc/lispref/nonascii.texi (Coding System Basics): Recommend
'emacs-internal' encoding for caching.

(cherry picked from commit 2cbea4f35cbfb25f53f23ebba81ffe89ce77b136)

diff --git a/doc/lispref/nonascii.texi b/doc/lispref/nonascii.texi
index 9a160ba0730830a56c750c832dcb00872b163219..1c5cc0e20b4cdaf6534014c9a85e485add158ef2 100644 (file)
--- a/doc/lispref/nonascii.texi
+++ b/doc/lispref/nonascii.texi
@@ -1135,7 +1135,10 @@ conversion happens, but different in that the result is multibyte
 data.  The name @code{emacs-internal} is an alias for
 @code{utf-8-emacs-unix} (so it forces no conversion of end-of-line,
 unlike @code{utf-8-emacs}, which can decode all 3 kinds of
-end-of-line conventions).
+end-of-line conventions).  Since this coding system can represent all
+the characters supported by Emacs in its buffers and strings, we
+recommend using it whenever saving text for internal purposes, such as
+caching.
 
 @defun coding-system-get coding-system property
 This function returns the specified property of the coding system