Re: unexpected behaviour of `with-output-to-string'

As for `with-current-buffer', the GNU version uses it to get the buffer contents, but we can do that with (buffer-string buffer). One should keep in mind that changing the current buffer is a fairly expensive operation; it requires, among other things, rebinding all buffer-local variables to their new values. If the result is available without changing the current buffer, the alternative method should be used. I propose this version, which is similar to FSF's, but with additional safety of using unwind-protect to guard against temp buffer leakage. (defmacro with-output-to-string (&rest body) "Execute BODY, return the text it sent to `standard-output', as a string." `(let ((standard-output (get-buffer-create (generate-new-buffer-name " *string-output*")))) (unwind-protect (progn ;; LET guards the value of standard-output should BODY ;; change it. (let ((standard-output standard-output)) ,＠body) (buffer-string standard-output)) (kill-buffer standard-output))))