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Diffstat (limited to 'lisp/emacs-lisp/byte-opt.el')
| -rw-r--r-- | lisp/emacs-lisp/byte-opt.el | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/lisp/emacs-lisp/byte-opt.el b/lisp/emacs-lisp/byte-opt.el index 10a50da4628..99e84e23ad8 100644 --- a/lisp/emacs-lisp/byte-opt.el +++ b/lisp/emacs-lisp/byte-opt.el @@ -1269,6 +1269,14 @@ See Info node `(elisp) Integer Basics'." form) form)) +(put 'cons 'byte-optimizer #'byte-optimize-cons) +(defun byte-optimize-cons (form) + ;; (cons X nil) => (list X) + (if (and (= (safe-length form) 3) + (null (nth 2 form))) + `(list ,(nth 1 form)) + form)) + ;; Fixme: delete-char -> delete-region (byte-coded) ;; optimize string-as-unibyte, string-as-multibyte, string-make-unibyte, ;; string-make-multibyte for constant args. |