From d032d5e7dfabfae60f3304da02c97cd1e189b9a2 Mon Sep 17 00:00:00 2001 From: Stefan Monnier Date: Tue, 1 Mar 2011 00:03:24 -0500 Subject: * doc/lispref/variables.texi (Scope): Mention the availability of lexbind. (Lexical Binding): New node. * doc/lispref/eval.texi (Eval): Add `eval's new `lexical' arg. * lisp/emacs-lisp/cconv.el (cconv-liftwhen): Increase threshold. (cconv-closure-convert-rec): Convert interactive spec in empty lexenv. (cconv-analyse-use): Improve unused vars warnings. (cconv-analyse-form): Analyze interactive spec in empty lexenv. * lisp/emacs-lisp/bytecomp.el (byte-compile-lambda): Always byte-compile the interactive spec in lexical-binding mode. (byte-compile-refresh-preloaded): Don't reload byte-compiler files. * lisp/custom.el (custom-initialize-default): Use defvar. (custom-declare-variable): Set the special-variable-p flag. * lisp/help-fns.el (help-make-usage): Drop leading underscores. * lisp/dired.el (dired-revert, dired-make-relative): Mark unused args. (dired-unmark-all-files): Remove unused var `query'. (dired-overwrite-confirmed): Declare. (dired-restore-desktop-buffer): Don't use dynamically scoped arg names. * lisp/mpc.el: Mark unused args. (mpc--faster-toggle): Remove unused var `songnb'. * lisp/server.el (server-kill-buffer-running): Move before first use. * lisp/minibuffer.el: Mark unused args. * src/callint.c (quotify_arg): Simplify the logic. (Fcall_interactively): Use lexical binding when evaluating the interactive spec of a lexically bound function. --- doc/lispref/eval.texi | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'doc/lispref/eval.texi') diff --git a/doc/lispref/eval.texi b/doc/lispref/eval.texi index d44fe5bb95b..74f3d9c48b9 100644 --- a/doc/lispref/eval.texi +++ b/doc/lispref/eval.texi @@ -585,6 +585,11 @@ occurrence in a program being run. On rare occasions, you may need to write code that evaluates a form that is computed at run time, such as after reading a form from text being edited or getting one from a property list. On these occasions, use the @code{eval} function. +Often @code{eval} is not needed and something else should be used instead. +For example, to get the value of a variable, while @code{eval} works, +@code{symbol-value} is preferable; or rather than store expressions +in a property list that then need to go through @code{eval}, it is better to +store functions instead that are then passed to @code{funcall}. The functions and variables described in this section evaluate forms, specify limits to the evaluation process, or record recently returned @@ -596,10 +601,13 @@ to store an expression in the data structure and evaluate it. Using functions provides the ability to pass information to them as arguments. -@defun eval form +@defun eval form &optional lexical This is the basic function evaluating an expression. It evaluates @var{form} in the current environment and returns the result. How the evaluation proceeds depends on the type of the object (@pxref{Forms}). +@var{lexical} if non-nil means to evaluate @var{form} using lexical scoping +rules (@pxref{Lexical Binding}) instead of the default dynamic scoping used +historically in Emacs Lisp. Since @code{eval} is a function, the argument expression that appears in a call to @code{eval} is evaluated twice: once as preparation before -- cgit v1.2.1