Mercurial > hg > xemacs-beta
diff lisp/cl-macs.el @ 5775:4004c3266c09
Transform #'princ to #'write-sequence at compile time if appropriate.
lisp/ChangeLog addition:
2013-12-22 Aidan Kehoe <kehoea@parhasard.net>
* cl-macs.el:
* cl-macs.el (princ): New compiler macro.
Transform #'princ to #'write-sequence if we can determine at
compile time that it is being passed a string. Initialising the
printer is expensive enough, but much of our code took this
approach because #'write-sequence wasn't available.
| author | Aidan Kehoe <kehoea@parhasard.net> |
|---|---|
| date | Sun, 22 Dec 2013 10:36:33 +0000 |
| parents | 165315eae1ab |
| children | bd644055ef44 |
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--- a/lisp/cl-macs.el Thu Dec 19 18:13:11 2013 +0000 +++ b/lisp/cl-macs.el Sun Dec 22 10:36:33 2013 +0000 @@ -3911,6 +3911,28 @@ (list* 'intersection (pop cl-keys) (pop cl-keys) :stable t cl-keys) form)) +(define-compiler-macro princ (&whole form object &optional stream) + "When passing `princ' a string, call `write-sequence' instead. + +This avoids the resource- and time-intensive initialization of the printer, +and functions equivalently. Such code will not run on 21.4, but 21.4 will +not normally encounter it, and the error message will be clear enough (that +`write-sequence' has a void function definition) in the odd event that it +does." + (cond ((not (<= 2 (length form) 3)) + form) + ((or (stringp object) + (member (car-safe object) + '(buffer-string buffer-substring concat format gettext + key-description make-string mapconcat + substitute-command-keys substring-no-properties + symbol-name text-char-description string))) + (cons 'write-sequence (cdr form))) + ((member (car-safe object) '(substring subseq)) + `(write-sequence ,(nth 1 object) ,stream :start ,(nth 2 object) + ,@(if (nth 3 object) `((:end ,(nth 3 object)))))) + (t form))) + (map nil #'(lambda (function) ;; There are byte codes for the two-argument versions of these