Examining the result of #'length: `eql', not `=', it's better style & cheaper 2011-03-08 Aidan Kehoe <kehoea@parhasard.net> * buff-menu.el (list-buffers-noselect): * byte-optimize.el (byte-optimize-identity): * byte-optimize.el (byte-optimize-if): * byte-optimize.el (byte-optimize-nth): * byte-optimize.el (byte-optimize-nthcdr): * bytecomp.el (byte-compile-warn-wrong-args): * bytecomp.el (byte-compile-two-args-19->20): * bytecomp.el (byte-compile-list): * bytecomp.el (byte-compile-beginning-of-line): * bytecomp.el (byte-compile-set): * bytecomp.el (byte-compile-set-default): * bytecomp.el (byte-compile-values): * bytecomp.el (byte-compile-values-list): * bytecomp.el (byte-compile-integerp): * bytecomp.el (byte-compile-multiple-value-list-internal): * bytecomp.el (byte-compile-throw): * cl-macs.el (cl-do-arglist): * cl-macs.el (cl-parse-loop-clause): * cl-macs.el (multiple-value-bind): * cl-macs.el (multiple-value-setq): * cl-macs.el (get-setf-method): * cmdloop.el (command-error): * cmdloop.el (y-or-n-p-minibuf): * cmdloop.el (yes-or-no-p-minibuf): * coding.el (unencodable-char-position): * cus-edit.el (custom-face-prompt): * cus-edit.el (custom-buffer-create-internal): * cus-edit.el (widget-face-action): * cus-edit.el (custom-group-value-create): * descr-text.el (describe-char-unicode-data): * dialog-gtk.el (popup-builtin-question-dialog): * dragdrop.el (experimental-dragdrop-drop-log-function): * dragdrop.el (experimental-dragdrop-drop-mime-default): * easymenu.el (easy-menu-add): * easymenu.el (easy-menu-remove): * faces.el (read-face-name): * faces.el (set-face-stipple): * files.el (file-name-non-special): * font.el (font-combine-fonts): * font.el (font-set-face-font): * font.el (font-parse-rgb-components): * font.el (font-rgb-color-p): * font.el (font-color-rgb-components): * gnuserv.el (gnuserv-edit-files): * help.el (key-or-menu-binding): * help.el (function-documentation-1): * help.el (function-documentation): * info.el (info): * isearch-mode.el (isearch-exit): * isearch-mode.el (isearch-edit-string): * isearch-mode.el (isearch-*-char): * isearch-mode.el (isearch-complete1): * ldap.el (ldap-encode-country-string): * ldap.el (ldap-decode-string): * minibuf.el (read-file-name-internal-1): * minibuf.el (read-non-nil-coding-system): * minibuf.el (get-user-response): * mouse.el (drag-window-divider): * mule/ccl.el: * mule/ccl.el (ccl-compile-if): * mule/ccl.el (ccl-compile-break): * mule/ccl.el (ccl-compile-repeat): * mule/ccl.el (ccl-compile-write-repeat): * mule/ccl.el (ccl-compile-call): * mule/ccl.el (ccl-compile-end): * mule/ccl.el (ccl-compile-read-multibyte-character): * mule/ccl.el (ccl-compile-write-multibyte-character): * mule/ccl.el (ccl-compile-translate-character): * mule/ccl.el (ccl-compile-mule-to-unicode): * mule/ccl.el (ccl-compile-unicode-to-mule): * mule/ccl.el (ccl-compile-lookup-integer): * mule/ccl.el (ccl-compile-lookup-character): * mule/ccl.el (ccl-compile-map-multiple): * mule/ccl.el (ccl-compile-map-single): * mule/devan-util.el (devanagari-compose-to-one-glyph): * mule/devan-util.el (devanagari-composition-component): * mule/mule-cmds.el (finish-set-language-environment): * mule/viet-util.el: * mule/viet-util.el (viet-encode-viscii-char): * multicast.el (open-multicast-group): * newcomment.el (comment-quote-nested): * newcomment.el (comment-region): * newcomment.el (comment-dwim): * regexp-opt.el (regexp-opt-group): * replace.el (map-query-replace-regexp): * specifier.el (derive-device-type-from-tag-set): * subr.el (skip-chars-quote): * test-harness.el (test-harness-from-buffer): * test-harness.el (batch-test-emacs): * wid-edit.el (widget-choice-action): * wid-edit.el (widget-symbol-prompt-internal): * wid-edit.el (widget-color-action): * window-xemacs.el (push-window-configuration): * window-xemacs.el (pop-window-configuration): * window.el (quit-window): * x-compose.el (electric-diacritic): It's better style, and cheaper (often one assembler instruction vs. a C funcall in the byte code), to use `eql' instead of `=' when it's clear what numerical type a given result will be. Change much of our code to do this, with the help of a byte-compiler change (not comitted) that looked for calls to #'length (which always returns an integer) in its args.

--- a/lisp/cl-macs.el	Tue Mar 08 22:32:49 2011 +0000
+++ b/lisp/cl-macs.el	Tue Mar 08 23:41:52 2011 +0000
@@ -428,7 +428,7 @@
 	  (or (eq p args) (setq minarg (list 'cdr minarg)))
 	  (setq p (cdr p)))
 	(if (memq (car p) '(nil &aux))
-	    (setq minarg (list '= (list 'length restarg)
+	    (setq minarg (list 'eql (list 'length restarg)
 			       (length (ldiff args p)))
 		  exactarg (not (eq args p)))))
       (while (and args (not (memq (car args) lambda-list-keywords)))
@@ -1265,7 +1265,7 @@
 		      (seq (cl-pop2 args))
 		      (temp-seq (gensym))
 		      (temp-idx (if (eq (car args) 'using)
-				    (if (and (= (length (cadr args)) 2)
+				    (if (and (eql (length (cadr args)) 2)
 					     (eq (caadr args) 'index))
 					(cadr (cl-pop2 args))
 				      (error "Bad `using' clause"))
@@ -1296,7 +1296,7 @@
 		(or (memq (car args) '(in of)) (error "Expected `of'"))
 		(let* ((table (cl-pop2 args))
 		       (other (if (eq (car args) 'using)
-				  (if (and (= (length (cadr args)) 2)
+				  (if (and (eql (length (cadr args)) 2)
 					   (memq (caadr args) hash-types)
 					   (not (eq (caadr args) word)))
 				      (cadr (cl-pop2 args))
@@ -1352,7 +1352,7 @@
 		(let* ((map (cl-pop2 args))
 		       other-word
 		       (other (if (eq (car args) 'using)
-				  (if (and (= (length (cadr args)) 2)
+				  (if (and (eql (length (cadr args)) 2)
 					   (memq (setq other-word (caadr args))
 						 key-types)
 					   (not (eq (caadr args) word)))
@@ -1880,7 +1880,7 @@
 Returns the value given by the last element of BODY."
   (if (null syms)
       `(progn ,form ,@body)
-    (if (= 1 (length syms))
+    (if (eql 1 (length syms))
         ;; Code written to deal with other "implementations" of multiple
         ;; values may have a one-element SYMS.
         `(let ((,(car syms) ,form))
@@ -1907,7 +1907,7 @@
   (if (null syms)
       ;; Never return multiple values from multiple-value-setq:
       (and form `(values ,form))
-    (if (= 1 (length syms))
+    (if (eql 1 (length syms))
         `(setq ,(car syms) ,form)
       (let ((temp (gensym)))
         `(let* ((,temp (multiple-value-list-internal 0 ,(length syms) ,form)))
@@ -2434,7 +2434,7 @@
 	       (or (and method
 			(let ((cl-macro-environment env))
 			  (setq method (apply method (cdr place))))
-			(if (and (consp method) (= (length method) 5))
+			(if (and (consp method) (eql (length method) 5))
 			    method
 			  (error "Setf-method for %s returns malformed method"
 				 func)))