Hello. We have had running in XEmacs for two years or more some routines I wrote to cleanly handle byte-compilation warnings. The problem was that many byte-compilation warnings were unavoidable when doing legitimate things. I came up with a clean solution to this problem and it has worked very well; all of the XEmacs core elisp code is now completely warning-free. I propose that this be incorporated into GNU Emacs as well. If agreed, I will sign papers and do whatever else is needed. I am the only author of this code. I'm attaching the doc strings. I would post the code itself but I gather rms does not want GNU Emacs developers to see non-kosher [i.e. not copyright-assigned] XEmacs code. If I'm wrong please let me know and I'll post the sources.  ;;; Functions to cleanly eliminate warnings about undefined functions ;;; or variables when the code knows what it's doing. These macros DO ;;; NOT rely on any byte-compiler changes, and thus can be copied into ;;; a package and used within it. ;; NOTE: As a result of the above requirement, the macros rely on ;; "tricks" to get the warnings suppressed. A cleaner way, of course, ;; would be to extend the byte compiler to provide a proper interface. ;; #### Should we require an unquoted symbol rather than a quoted one, ;; as we currently do? The quoting gets no generality, as `eval' is ;; called at compile time. But most functions and macros want quoted ;; arguments, and I find it extremely confusing to deal with cases ;; such as `throw' requiring a quoted argument but `block' an unquoted ;; one. (put 'with-boundp 'lisp-indent-function 1) (defmacro with-boundp (variables &rest body) "Evaluate BODY, but do not issue bytecomp warnings about VARIABLES undefined. VARIABLES can be a symbol or a list of symbols and must be quoted. When compiling this file, the warnings `reference to free variable VARIABLE' and `assignment to free variable VARIABLE' will not occur anywhere in BODY, for any of the listed variables. This is a clean way to avoid such warnings. See also `if-boundp', `when-boundp', and `and-boundp' (ways to conditionalize on a variable being bound and avoid warnings), `declare-boundp' (issue a variable call without warnings), and `globally-declare-boundp' (avoid warnings throughout a file about a variable)." (put 'if-boundp 'lisp-indent-function 2) (defmacro if-boundp (variable then &rest else) "Equivalent to (if (boundp VARIABLE) THEN ELSE) but handles bytecomp warnings. VARIABLE should be a quoted symbol. When compiling this file, the warnings `reference to free variable VARIABLE' and `assignment to free variable VARIABLE' will not occur anywhere in the if-statement. This is a clean way to avoid such warnings. See also `with-boundp' and friends." (put 'when-boundp 'lisp-indent-function 1) (defmacro when-boundp (variable &rest body) "Equivalent to (when (boundp VARIABLE) BODY) but handles bytecomp warnings. VARIABLE should be a quoted symbol. When compiling this file, the warnings `reference to free variable VARIABLE' and `assignment to free variable VARIABLE' will not occur anywhere in the when-statement. This is a clean way to avoid such warnings. See also `with-boundp' and friends." (put 'and-boundp 'lisp-indent-function 1) (defmacro and-boundp (variable &rest args) "Equivalent to (and (boundp VARIABLE) ARGS) but handles bytecomp warnings. VARIABLE should be a quoted symbol. When compiling this file, the warnings `reference to free variable VARIABLE' and `assignment to free variable VARIABLE' will not occur anywhere in the and-statement. This is a clean way to avoid such warnings. See also `with-boundp' and friends." (defmacro declare-boundp (variable) "Evaluate VARIABLE without bytecomp warnings about the symbol. Sample usage is (declare-boundp gpm-minor-mode) which is equivalent to (with-boundp 'gpm-minor-mode gpm-minor-mode) See also `with-boundp' and friends." (defmacro globally-declare-boundp (variables) "Declare that all free uses of VARIABLES in this file are valid. VARIABLES can be a symbol or a list of symbols and must be quoted. When compiling this file, the warnings `reference to free variable VARIABLE' and `assignment to free variable VARIABLE' will not occur regardless of where references to VARIABLE occur in the file. In general, you should *NOT* use this; use `with-boundp' or its friends to wrap individual uses, as necessary. That way, you're more likely to remember to put in the explicit checks for the variable's existence that are usually necessary. However, `globally-declare-boundp' is better in some circumstances, such as when writing an ELisp package that makes integral use of optionally-compiled-in functionality (typically, an interface onto a system library) and checks for the existence of the functionality at some entry point to the package. See `globally-declare-fboundp' for more information." (put 'with-fboundp 'lisp-indent-function 1) (defmacro with-fboundp (functions &rest body) "Evaluate BODY, but do not issue bytecomp warnings about FUNCTIONS undefined. FUNCTIONS can be a symbol or a list of symbols and must be quoted. When compiling this file, the warning `the function FUNCTION is not known to be defined' will not occur anywhere in BODY, for any of the listed functions. This is a clean way to avoid such warnings. See also `if-fboundp', `when-fboundp', and `and-fboundp' (ways to conditionalize on a function being bound and avoid warnings), `declare-fboundp' (issue a function call without warnings), and `globally-declare-fboundp' (avoid warnings throughout a file about a function)." (put 'if-fboundp 'lisp-indent-function 2) (defmacro if-fboundp (function then &rest else) "Equivalent to (if (fboundp FUNCTION) THEN ELSE) but handles bytecomp warnings. FUNCTION should be a quoted symbol. When compiling this file, the warning `the function FUNCTION is not known to be defined' will not occur anywhere in the if-statement. This is a clean way to avoid such warnings. See also `with-fboundp' and friends." (put 'when-fboundp 'lisp-indent-function 1) (defmacro when-fboundp (function &rest body) "Equivalent to (when (fboundp FUNCTION) BODY) but handles bytecomp warnings. FUNCTION should be a quoted symbol. When compiling this file, the warning `the function FUNCTION is not known to be defined' will not occur anywhere in the when-statement. This is a clean way to avoid such warnings. See also `with-fboundp' and friends." (put 'and-fboundp 'lisp-indent-function 1) (defmacro and-fboundp (function &rest args) "Equivalent to (and (fboundp FUNCTION) ARGS) but handles bytecomp warnings. FUNCTION should be a quoted symbol. When compiling this file, the warning `the function FUNCTION is not known to be defined' will not occur anywhere in the and-statement. This is a clean way to avoid such warnings. See also `with-fboundp' and friends." (defmacro declare-fboundp (form) "Execute FORM (a function call) without bytecomp warnings about the call. Sample usage is (declare-fboundp (x-keysym-on-keyboard-sans-modifiers-p 'backspace)) which is equivalent to (with-fboundp 'x-keysym-on-keyboard-sans-modifiers-p (x-keysym-on-keyboard-sans-modifiers-p 'backspace)) See also `with-fboundp' and friends." (defmacro globally-declare-fboundp (functions) "Declare that all calls to function FUNCTIONS in this file are valid. FUNCTIONS can be a symbol or a list of symbols and must be quoted. When compiling this file, the warning `the function FUNCTION is not known to be defined' will not occur regardless of where calls to FUNCTION occur in the file. In general, you should *NOT* use this; use `with-fboundp' or its friends to wrap individual uses, as necessary. That way, you're more likely to remember to put in the explicit checks for the function's existence that are usually necessary. However, `globally-declare-fboundp' is better in some circumstances, such as when writing an ELisp package that makes integral use of optionally-compiled-in functionality (typically, an interface onto a system library) and checks for the existence of the functionality at some entry point to the package. The file `ldap.el' is a good example: It provides a layer on top of the optional LDAP ELisp primitives, makes calls to them throughout its code, and verifies the presence of LDAP support at load time. Putting calls to `declare-fboundp' throughout the code would be a major annoyance." (defmacro with-byte-compiler-warnings-suppressed (type &rest body) "Evaluate BODY, but do not issue bytecomp warnings TYPE. TYPE should be one of `redefine', `callargs', `subr-callargs', `free-vars', `unresolved', `unused-vars', `obsolete', or `pedantic', or a list of one or more of these symbols. (See `byte-compile-warnings'.) TYPE must be quoted. NOTE: You should *NOT* under normal circumstances be using this! There are better ways of avoiding most of these warnings. In particular: -- use (declare (special ...)) if you are making use of dynamically-scoped variables. -- use `with-fboundp' and friends to avoid warnings about undefined functions when you know the function actually exists. -- use `with-boundp' and friends to avoid warnings about undefined variables when you know the variable actually exists. -- use `with-obsolete-variable' or `with-obsolete-function' if you are purposely using such a variable or function." (put 'with-obsolete-variable 'lisp-indent-function 1) (defmacro with-obsolete-variable (symbol &rest body) "Evaluate BODY but do not warn about usage of obsolete variable SYMBOL. SYMBOL must be quoted and can be a list of SYMBOLS. See also `with-obsolete-function'." (put 'with-obsolete-function 'lisp-indent-function 1) (defmacro with-obsolete-function (symbol &rest body) "Evaluate BODY but do not warn about usage of obsolete function SYMBOL. SYMBOL must be quoted and can be a list of SYMBOLS. See also `with-obsolete-variable'."