standard @code{setf} facility, and a number of looping and conditional
constructs.
-@c FIXME
-@c flet is not cl-flet.
@menu
* Assignment:: The @code{cl-psetq} form.
* Generalized Variables:: Extensions to generalized variables.
-* Variable Bindings:: @code{cl-progv}, @code{flet}, @code{cl-macrolet}.
+* Variable Bindings:: @code{cl-progv}, @code{cl-flet}, @code{cl-macrolet}.
* Conditionals:: @code{cl-case}, @code{cl-typecase}.
* Blocks and Exits:: @code{cl-block}, @code{cl-return}, @code{cl-return-from}.
* Iteration:: @code{cl-do}, @code{cl-dotimes}, @code{cl-dolist}, @code{cl-do-symbols}.
@menu
* Dynamic Bindings:: The @code{cl-progv} form.
-* Function Bindings:: @code{flet} and @code{labels}.
+* Function Bindings:: @code{cl-flet} and @code{cl-labels}.
* Macro Bindings:: @code{cl-macrolet} and @code{cl-symbol-macrolet}.
@end menu
These forms make @code{let}-like bindings to functions instead
of variables.
-@defmac flet (bindings@dots{}) forms@dots{}
+@defmac cl-flet (bindings@dots{}) forms@dots{}
This form establishes @code{let}-style bindings on the function
cells of symbols rather than on the value cells. Each @var{binding}
must be a list of the form @samp{(@var{name} @var{arglist}
@var{forms}@dots{})}, which defines a function exactly as if
it were a @code{cl-defun} form. The function @var{name} is defined
-accordingly for the duration of the body of the @code{flet}; then
+accordingly for the duration of the body of the @code{cl-flet}; then
the old function definition, or lack thereof, is restored.
-While @code{flet} in Common Lisp establishes a lexical binding of
-@var{name}, Emacs Lisp @code{flet} makes a dynamic binding. The
-result is that @code{flet} affects indirect calls to a function as
-well as calls directly inside the @code{flet} form itself.
-
-You can use @code{flet} to disable or modify the behavior of a
+You can use @code{cl-flet} to disable or modify the behavior of a
function in a temporary fashion. This will even work on Emacs
primitives, although note that some calls to primitive functions
internal to Emacs are made without going through the symbol's
-function cell, and so will not be affected by @code{flet}. For
+function cell, and so will not be affected by @code{cl-flet}. For
example,
@example
-(flet ((message (&rest args) (push args saved-msgs)))
- (do-something))
+(cl-flet ((message (&rest args) (push args saved-msgs)))
+ (do-something))
@end example
This code attempts to replace the built-in function @code{message}
direct C-language calls to the message routines rather than going
through the Lisp @code{message} function.
-@c Bug#411.
-Also note that many primitives (e.g. @code{+}) have special byte-compile
-handling. Attempts to redefine such functions using @code{flet} will
-fail if byte-compiled. In such cases, use @code{labels} instead.
-
-Functions defined by @code{flet} may use the full Common Lisp
+Functions defined by @code{cl-flet} may use the full Common Lisp
argument notation supported by @code{cl-defun}; also, the function
body is enclosed in an implicit block as if by @code{cl-defun}.
@xref{Program Structure}.
@end defmac
-@defmac labels (bindings@dots{}) forms@dots{}
-The @code{labels} form is like @code{flet}, except that it
-makes lexical bindings of the function names rather than
-dynamic bindings. (In true Common Lisp, both @code{flet} and
-@code{labels} make lexical bindings of slightly different sorts;
-since Emacs Lisp is dynamically bound by default, it seemed
-more appropriate for @code{flet} also to use dynamic binding.
-The @code{labels} form, with its lexical binding, is fully
-compatible with Common Lisp.)
+@defmac cl-labels (bindings@dots{}) forms@dots{}
+The @code{cl-labels} form is like @code{cl-flet}, except that
+the function bindings can be recursive. The scoping is lexical,
+but you can only capture functions in closures if
+@code{lexical-binding} is non-@code{nil}.
+@xref{Closures,,,elisp,GNU Emacs Lisp Reference Manual}, and
+@ref{Using Lexical Binding,,,elisp,GNU Emacs Lisp Reference Manual}.
Lexical scoping means that all references to the named
functions must appear physically within the body of the
-@code{labels} form. References may appear both in the body
-@var{forms} of @code{labels} itself, and in the bodies of
-the functions themselves. Thus, @code{labels} can define
-local recursive functions, or mutually-recursive sets of
-functions.
+@code{cl-labels} form. References may appear both in the body
+@var{forms} of @code{cl-labels} itself, and in the bodies of
+the functions themselves. Thus, @code{cl-labels} can define
+local recursive functions, or mutually-recursive sets of functions.
A ``reference'' to a function name is either a call to that
function, or a use of its name quoted by @code{quote} or
These forms create local macros and ``symbol macros''.
@defmac cl-macrolet (bindings@dots{}) forms@dots{}
-This form is analogous to @code{flet}, but for macros instead of
+This form is analogous to @code{cl-flet}, but for macros instead of
functions. Each @var{binding} is a list of the same form as the
arguments to @code{cl-defmacro} (i.e., a macro name, argument list,
and macro-expander forms). The macro is defined accordingly for
called.
Internally, this package uses lexical binding so that such problems do
-not occur. @xref{Lexical Bindings}, for a description of the obsolete
+not occur. @xref{Obsolete Lexical Binding}, for a description of the obsolete
@code{lexical-let} form that emulates a Common Lisp-style lexical
binding when dynamic binding is in use.
in exactly the same way.
@menu
-* Lexical Bindings:: An approximation of lexical binding.
-* Obsolete Lexical Macros:: Obsolete macros using lexical-let.
+* Obsolete Lexical Binding:: An approximation of lexical binding.
+* Obsolete Macros:: Obsolete macros.
* Obsolete Setf Customization:: Obsolete ways to customize setf.
@end menu
-@node Lexical Bindings
-@appendixsec Lexical Bindings
+@node Obsolete Lexical Binding
+@appendixsec Obsolete Lexical Binding
The following macros are extensions to Common Lisp, where all bindings
are lexical unless declared otherwise. These features are likewise
are made sequentially in the manner of @code{let*}.
@end defmac
-@node Obsolete Lexical Macros
-@appendixsec Macros Defined Using Lexical-Let
+@node Obsolete Macros
+@appendixsec Obsolete Macros
-The following macros are defined using @code{lexical-let}.
-They are replaced by versions with a @samp{cl-} prefix that use true
-lexical binding (and hence rely on @code{lexical-binding} being set to
-@code{t} in code using them).
+The following macros are obsolete, and are replaced by versions with
+a @samp{cl-} prefix that do not behave in exactly the same way.
+Consequently, the @file{cl.el} versions are not simply aliases to the
+@file{cl-lib.el} versions.
@defmac flet (bindings@dots{}) forms@dots{}
-Replaced by @code{cl-flet} (@pxref{Function Bindings})
-or @code{cl-letf} (@pxref{Modify Macros}).
+This macro is replaced by @code{cl-flet} (@pxref{Function Bindings}),
+which behaves the same way as Common Lisp's @code{flet}.
+This @code{flet} takes the same arguments as @code{cl-flet}, but does
+not behave in precisely the same way.
+
+While @code{flet} in Common Lisp establishes a lexical function
+binding, this @code{flet} makes a dynamic binding (it dates from a
+time before Emacs had lexical binding). The result is
+that @code{flet} affects indirect calls to a function as well as calls
+directly inside the @code{flet} form itself.
+
+@c Bug#411.
+Note that many primitives (e.g. @code{+}) have special byte-compile
+handling. Attempts to redefine such functions using @code{flet} will
+fail if byte-compiled.
+@c Or cl-flet.
+@c In such cases, use @code{labels} instead.
@end defmac
@defmac labels (bindings@dots{}) forms@dots{}
-Replaced by @code{cl-labels} (@pxref{Function Bindings}).
+This macro is replaced by @code{cl-labels} (@pxref{Function Bindings}),
+which behaves the same way as Common Lisp's @code{labels}.
+This @code{labels} takes the same arguments as @code{cl-labels}, but
+does not behave in precisely the same way.
+
+This version of @code{labels} uses the obsolete @code{lexical-let}
+form (@pxref{Obsolete Lexical Binding}), rather than the true
+lexical binding that @code{cl-labels} uses.
@end defmac
@defmac letf (bindings@dots{}) forms@dots{}
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