with @code{setq-default}.
@strong{Warning:} When a variable has buffer-local values in one or
-more buffers, you can get Emacs very confused by binding the variable
-with @code{let}, changing to a different current buffer in which a
-different binding is in effect, and then exiting the @code{let}. This
-can scramble the values of the buffer-local and default bindings.
+more buffers, binding the variable with @code{let} and changing to a
+different current buffer in which a different binding is in
+effect, and then exiting the @code{let}, the variable may not be
+restored to the value it had before the @code{let}.
To preserve your sanity, avoid using a variable in that way. If you
use @code{save-excursion} around each piece of code that changes to a
@example
@group
-(setq foo 'b)
+(setq foo 'g)
(set-buffer "a")
(make-local-variable 'foo)
@end group
(setq foo 'a)
(let ((foo 'temp))
+ ;; foo @result{} 'temp ; @r{let binding in buffer @samp{a}}
(set-buffer "b")
+ ;; foo @result{} 'g ; @r{the global value since foo is not local in @samp{b}}
@var{body}@dots{})
@group
-foo @result{} 'a ; @r{The old buffer-local value from buffer @samp{a}}
- ; @r{is now the default value.}
+foo @result{} 'a ; @r{we are still in buffer @samp{b}, but exiting the let}
+ ; @r{restored the local value in buffer @samp{a}}
@end group
@group
-(set-buffer "a")
-foo @result{} 'temp ; @r{The local @code{let} value that should be gone}
- ; @r{is now the buffer-local value in buffer @samp{a}.}
+(set-buffer "a") ; @r{This can be seen here:}
+foo @result{} 'a ; @r{we are back to the local value in buffer @samp{a}}
@end group
@end example