diff options
Diffstat (limited to 'lisp/emacs-lisp/macroexp.el')
| -rw-r--r-- | lisp/emacs-lisp/macroexp.el | 82 |
1 files changed, 65 insertions, 17 deletions
diff --git a/lisp/emacs-lisp/macroexp.el b/lisp/emacs-lisp/macroexp.el index 82a8cd2d777..e842222b7c3 100644 --- a/lisp/emacs-lisp/macroexp.el +++ b/lisp/emacs-lisp/macroexp.el @@ -127,7 +127,7 @@ and also to avoid outputting the warning during normal execution." (cond ((null msg) form) ((macroexp--compiling-p) - (if (gethash form macroexp--warned) + (if (and (consp form) (gethash form macroexp--warned)) ;; Already wrapped this exp with a warning: avoid inf-looping ;; where we keep adding the same warning onto `form' because ;; macroexpand-all gets right back to macroexpanding `form'. @@ -138,9 +138,10 @@ and also to avoid outputting the warning during normal execution." ,form))) (t (unless compile-only - (message "%s%s" (if (stringp load-file-name) - (concat (file-relative-name load-file-name) ": ") - "") + (message "%sWarning: %s" + (if (stringp load-file-name) + (concat (file-relative-name load-file-name) ": ") + "") msg)) form)))) @@ -180,8 +181,9 @@ and also to avoid outputting the warning during normal execution." (defun macroexp-macroexpand (form env) "Like `macroexpand' but checking obsolescence." - (let ((new-form - (macroexpand form env))) + (let* ((macroexpand-all-environment env) + (new-form + (macroexpand form env))) (if (and (not (eq form new-form)) ;It was a macro call. (car-safe form) (symbolp (car form)) @@ -239,9 +241,22 @@ Assumes the caller has bound `macroexpand-all-environment'." form)) (`(,(and fun `(lambda . ,_)) . ,args) ;; Embedded lambda in function position. - (macroexp--cons (macroexp--all-forms fun 2) - (macroexp--all-forms args) - form)) + ;; If the byte-optimizer is loaded, try to unfold this, + ;; i.e. rewrite it to (let (<args>) <body>). We'd do it in the optimizer + ;; anyway, but doing it here (i.e. earlier) can sometimes avoid the + ;; creation of a closure, thus resulting in much better code. + (let ((newform (if (not (fboundp 'byte-compile-unfold-lambda)) + 'macroexp--not-unfolded + ;; Don't unfold if byte-opt is not yet loaded. + (byte-compile-unfold-lambda form)))) + (if (or (eq newform 'macroexp--not-unfolded) + (eq newform form)) + ;; Unfolding failed for some reason, avoid infinite recursion. + (macroexp--cons (macroexp--all-forms fun 2) + (macroexp--all-forms args) + form) + (macroexp--expand-all newform)))) + ;; The following few cases are for normal function calls that ;; are known to funcall one of their arguments. The byte ;; compiler has traditionally handled these functions specially @@ -255,17 +270,21 @@ Assumes the caller has bound `macroexpand-all-environment'." (macroexp--warn-and-return (format "%s quoted with ' rather than with #'" (list 'lambda (nth 1 f) '...)) - (macroexp--expand-all `(,fun ,f . ,args)))) + (macroexp--expand-all `(,fun #',f . ,args)))) ;; Second arg is a function: (`(,(and fun (or 'sort)) ,arg1 ',(and f `(lambda . ,_)) . ,args) (macroexp--warn-and-return (format "%s quoted with ' rather than with #'" (list 'lambda (nth 1 f) '...)) - (macroexp--expand-all `(,fun ,arg1 ,f . ,args)))) - (`(funcall #',(and f (pred symbolp)) . ,args) - ;; Rewrite (funcall #'foo bar) to (foo bar), in case `foo' - ;; has a compiler-macro. - (macroexp--expand-all `(,f . ,args))) + (macroexp--expand-all `(,fun ,arg1 #',f . ,args)))) + (`(funcall ,exp . ,args) + (let ((eexp (macroexp--expand-all exp)) + (eargs (macroexp--all-forms args))) + ;; Rewrite (funcall #'foo bar) to (foo bar), in case `foo' + ;; has a compiler-macro, or to unfold it. + (pcase eexp + (`#',f (macroexp--expand-all `(,f . ,eargs))) + (_ `(funcall ,eexp . ,eargs))))) (`(,func . ,_) ;; Macro expand compiler macros. This cannot be delayed to ;; byte-optimize-form because the output of the compiler-macro can @@ -358,12 +377,12 @@ Never returns an empty list." (t `(cond (,test ,@(macroexp-unprogn then)) (,(nth 1 else) ,@(macroexp-unprogn (nth 2 else))) - (t ,@(nthcdr 3 else)))))) + ,@(let ((def (nthcdr 3 else))) (if def `((t ,@def)))))))) ((eq (car-safe else) 'cond) `(cond (,test ,@(macroexp-unprogn then)) ,@(cdr else))) ;; Invert the test if that lets us reduce the depth of the tree. ((memq (car-safe then) '(if cond)) (macroexp-if `(not ,test) else then)) - (t `(if ,test ,then ,@(macroexp-unprogn else))))) + (t `(if ,test ,then ,@(if else (macroexp-unprogn else)))))) (defmacro macroexp-let2 (test sym exp &rest body) "Evaluate BODY with SYM bound to an expression for EXP's value. @@ -480,6 +499,35 @@ itself or not." v (list 'quote v))) +(defun macroexp--fgrep (bindings sexp) + "Return those of the BINDINGS which might be used in SEXP. +It is used as a poor-man's \"free variables\" test. It differs from a true +test of free variables in the following ways: +- It does not distinguish variables from functions, so it can be used + both to detect whether a given variable is used by SEXP and to + detect whether a given function is used by SEXP. +- It does not actually know ELisp syntax, so it only looks for the presence + of symbols in SEXP and can't distinguish if those symbols are truly + references to the given variable (or function). That can make the result + include bindings which actually aren't used. +- For the same reason it may cause the result to fail to include bindings + which will be used if SEXP is not yet fully macro-expanded and the + use of the binding will only be revealed by macro expansion." + (let ((res '())) + (while (and (consp sexp) bindings) + (dolist (binding (macroexp--fgrep bindings (pop sexp))) + (push binding res) + (setq bindings (remove binding bindings)))) + (if (or (vectorp sexp) (byte-code-function-p sexp)) + ;; With backquote, code can appear within vectors as well. + ;; This wouldn't be needed if we `macroexpand-all' before + ;; calling macroexp--fgrep, OTOH. + (macroexp--fgrep bindings (mapcar #'identity sexp)) + (let ((tmp (assq sexp bindings))) + (if tmp + (cons tmp res) + res))))) + ;;; Load-time macro-expansion. ;; Because macro-expansion used to be more lazy, eager macro-expansion |