0.7.9.9:

[sbcl.git] / src / code / macros.lisp

diff --git a/src/code/macros.lisp b/src/code/macros.lisp
index 8fb9125..2574cac 100644 (file)
--- a/src/code/macros.lisp
+++ b/src/code/macros.lisp
@@ -28,11 +28,11 @@
   #!+sb-doc
   "Signals an error if the value of test-form is nil. Continuing from this
    error using the CONTINUE restart will allow the user to alter the value of
   #!+sb-doc
   "Signals an error if the value of test-form is nil. Continuing from this
    error using the CONTINUE restart will allow the user to alter the value of

-   some locations known to SETF, starting over with test-form. Returns nil."
+   some locations known to SETF, starting over with test-form. Returns NIL."

   `(do () (,test-form)
      (assert-error ',test-form ',places ,datum ,@arguments)
   `(do () (,test-form)
      (assert-error ',test-form ',places ,datum ,@arguments)

-     ,@(mapcar #'(lambda (place)
-                  `(setf ,place (assert-prompt ',place ,place)))
+     ,@(mapcar (lambda (place)
+                `(setf ,place (assert-prompt ',place ,place)))

               places)))
 
 (defun assert-prompt (name value)
               places)))
 
 (defun assert-prompt (name value)

@@ -56,99 +56,74 @@
 ;;;
 ;;; FIXME: In reality, this restart cruft is needed hardly anywhere in
 ;;; the system. Write NEED and NEED-TYPE to replace ASSERT and
 ;;;
 ;;; FIXME: In reality, this restart cruft is needed hardly anywhere in
 ;;; the system. Write NEED and NEED-TYPE to replace ASSERT and

-;;; CHECK-TYPE inside the system.
+;;; CHECK-TYPE inside the system. (CL:CHECK-TYPE must still be
+;;; defined, since it's specified by ANSI and it is sometimes nice for
+;;; whipping up little things. But as far as I can tell it's not
+;;; usually very helpful deep inside the guts of a complex system like
+;;; SBCL.)

 ;;;
 ;;; CHECK-TYPE-ERROR isn't defined until a later file because it uses
 ;;; the macro RESTART-CASE, which isn't defined until a later file.
 (defmacro-mundanely check-type (place type &optional type-string)
   #!+sb-doc
 ;;;
 ;;; CHECK-TYPE-ERROR isn't defined until a later file because it uses
 ;;; the macro RESTART-CASE, which isn't defined until a later file.
 (defmacro-mundanely check-type (place type &optional type-string)
   #!+sb-doc

-  "Signals a restartable error of type TYPE-ERROR if the value of PLACE is
+  "Signal a restartable error of type TYPE-ERROR if the value of PLACE is

   not of the specified type. If an error is signalled and the restart is
   not of the specified type. If an error is signalled and the restart is

-  used to return, the
-  return if the
-   STORE-VALUE is invoked. It will store into PLACE and start over."
+  used to return, this can only return if the STORE-VALUE restart is
+  invoked. In that case it will store into PLACE and start over."

   (let ((place-value (gensym)))
   (let ((place-value (gensym)))

-    `(do ((,place-value ,place))
+    `(do ((,place-value ,place ,place))

         ((typep ,place-value ',type))
        (setf ,place
             (check-type-error ',place ,place-value ',type ,type-string)))))
         ((typep ,place-value ',type))
        (setf ,place
             (check-type-error ',place ,place-value ',type ,type-string)))))

-
-#!+high-security-support
-(defmacro-mundanely check-type-var (place type-var &optional type-string)
-  #!+sb-doc
-  "Signals an error of type TYPE-ERROR if the contents of PLACE are not of the
-   specified type to which the TYPE-VAR evaluates. If an error is signaled,
-   this can only return if STORE-VALUE is invoked. It will store into PLACE
-   and start over."
-  (let ((place-value (gensym))
-       (type-value (gensym)))
-    `(do ((,place-value ,place)
-         (,type-value  ,type-var))
-        ((typep ,place-value ,type-value))
-       (setf ,place
-            (check-type-error ',place ,place-value ,type-value ,type-string)))))

 \f
 \f

-;;;; DEFCONSTANT
+;;;; DEFINE-SYMBOL-MACRO

 
 

-(defmacro-mundanely defconstant (name value &optional documentation)
-  #!+sb-doc
-  "For defining global constants. The DEFCONSTANT says that the value
-  is constant and may be compiled into code. If the variable already has
-  a value, and this is not EQL to the init, the code is not portable
-  (undefined behavior). The third argument is an optional documentation
-  string for the variable."
+(defmacro-mundanely define-symbol-macro (name expansion)

   `(eval-when (:compile-toplevel :load-toplevel :execute)
   `(eval-when (:compile-toplevel :load-toplevel :execute)

-     (sb!c::%defconstant ',name ,value ',documentation)))
+    (sb!c::%define-symbol-macro ',name ',expansion)))

 
 

-;;; (to avoid "undefined function" warnings when cross-compiling)
-(sb!xc:proclaim '(ftype function sb!c::%defconstant))
-
-;;; the guts of DEFCONSTANT
-(defun sb!c::%defconstant (name value doc)
-  (/show "doing %DEFCONSTANT" name value doc)
+(defun sb!c::%define-symbol-macro (name expansion)

   (unless (symbolp name)
   (unless (symbolp name)

-    (error "constant name not a symbol: ~S" name))
-  (about-to-modify name)
-  (let ((kind (info :variable :kind name)))
-    (case kind
-      (:constant
-       ;; Note 1: This behavior (discouraging any non-EQL
-       ;; modification) is unpopular, but it is specified by ANSI
-       ;; (i.e. ANSI says a non-EQL change has undefined
-       ;; consequences). If people really want bindings which are
-       ;; constant in some sense other than EQL, I suggest either just
-       ;; using DEFVAR (which is usually appropriate, despite the
-       ;; un-mnemonic name), or defining something like
-       ;; SB-INT:DEFCONSTANT-EQX (which is occasionally more
-       ;; appropriate). -- WHN 2000-11-03
-       (unless (eql value
-                   (info :variable :constant-value name))
-        (cerror "Go ahead and change the value."
-                "The constant ~S is being redefined."
-                name)))
-      (:global
-       ;; (This is OK -- undefined variables are of this kind. So we
-       ;; don't warn or error or anything, just fall through.)
-       )
-      (t (warn "redefining ~(~A~) ~S to be a constant" kind name))))
-  (when doc
-    (setf (fdocumentation name 'variable) doc))
-  (setf (symbol-value name) value)
-  (setf (info :variable :kind name) :constant)
-  (setf (info :variable :constant-value name) value)
+    (error 'simple-type-error :datum name :expected-type 'symbol
+          :format-control "Symbol macro name is not a symbol: ~S."
+          :format-arguments (list name)))
+  (ecase (info :variable :kind name)
+    ((:macro :global nil)
+     (setf (info :variable :kind name) :macro)
+     (setf (info :variable :macro-expansion name) expansion))
+    (:special
+     (error 'simple-program-error
+           :format-control "Symbol macro name already declared special: ~S."
+           :format-arguments (list name)))
+    (:constant
+     (error 'simple-program-error
+           :format-control "Symbol macro name already declared constant: ~S."
+           :format-arguments (list name))))

   name)
   name)

+

 \f
 ;;;; DEFINE-COMPILER-MACRO
 
 \f
 ;;;; DEFINE-COMPILER-MACRO
 

-;;; FIXME: The logic here for handling compiler macros named (SETF
-;;; FOO) was added after the fork from SBCL, is not well tested, and
-;;; may conflict with subtleties of the ANSI standard. E.g. section
-;;; "3.2.2.1 Compiler Macros" says that creating a lexical binding for
-;;; a function name shadows a compiler macro, and it's not clear that
-;;; that works with this version. It should be tested.

 (defmacro-mundanely define-compiler-macro (name lambda-list &body body)
   #!+sb-doc
   "Define a compiler-macro for NAME."
 (defmacro-mundanely define-compiler-macro (name lambda-list &body body)
   #!+sb-doc
   "Define a compiler-macro for NAME."

+  (legal-fun-name-or-type-error name)
+  (when (consp name)
+    ;; It's fairly clear that the user intends the compiler macro to
+    ;; expand when he does (SETF (FOO ...) X). And that's even a
+    ;; useful and reasonable thing to want. Unfortunately,
+    ;; (SETF (FOO ...) X) macroexpands into (FUNCALL (SETF FOO) X ...),
+    ;; and it's not at all clear that it's valid to expand a FUNCALL form,
+    ;; and the ANSI standard doesn't seem to say anything else which
+    ;; would justify us expanding the compiler macro the way the user
+    ;; wants. So instead we rely on 3.2.2.1.3 "When Compiler Macros Are
+    ;; Used" which says they never have to be used, so by ignoring such
+    ;; macros we're erring on the safe side. But any user who does
+    ;; (DEFINE-COMPILER-MACRO (SETF FOO) ...) could easily be surprised
+    ;; by this way of complying with a rather screwy aspect of the ANSI
+    ;; spec, so at least we can warn him...
+    (sb!c::compiler-style-warn
+     "defining compiler macro of (SETF ...), which will not be expanded"))

   (let ((whole (gensym "WHOLE-"))
        (environment (gensym "ENV-")))
     (multiple-value-bind (body local-decs doc)
   (let ((whole (gensym "WHOLE-"))
        (environment (gensym "ENV-")))
     (multiple-value-bind (body local-decs doc)

@@ -156,16 +131,11 @@
                        :environment environment)
       (let ((def `(lambda (,whole ,environment)
                    ,@local-decs
                        :environment environment)
       (let ((def `(lambda (,whole ,environment)
                    ,@local-decs

-                   (block ,(function-name-block-name name)
+                   (block ,(fun-name-block-name name)

                      ,body))))
        `(sb!c::%define-compiler-macro ',name #',def ',lambda-list ,doc)))))
 (defun sb!c::%define-compiler-macro (name definition lambda-list doc)
                      ,body))))
        `(sb!c::%define-compiler-macro ',name #',def ',lambda-list ,doc)))))
 (defun sb!c::%define-compiler-macro (name definition lambda-list doc)

-  ;; FIXME: Why does this have to be an interpreted function? Shouldn't
-  ;; it get compiled?
-  (assert (sb!eval:interpreted-function-p definition))
-  (setf (sb!eval:interpreted-function-name definition)
-       (format nil "DEFINE-COMPILER-MACRO ~S" name))
-  (setf (sb!eval:interpreted-function-arglist definition) lambda-list)
+  (declare (ignore lambda-list))

   (sb!c::%%define-compiler-macro name definition doc))
 (defun sb!c::%%define-compiler-macro (name definition doc)
   (setf (sb!xc:compiler-macro-function name) definition)
   (sb!c::%%define-compiler-macro name definition doc))
 (defun sb!c::%%define-compiler-macro (name definition doc)
   (setf (sb!xc:compiler-macro-function name) definition)

@@ -203,10 +173,13 @@
       (destructuring-bind (keyoid &rest forms) case
        (cond ((memq keyoid '(t otherwise))
               (if errorp
       (destructuring-bind (keyoid &rest forms) case
        (cond ((memq keyoid '(t otherwise))
               (if errorp

-                  (error 'simple-program-error
-                         :format-control
-                         "No default clause is allowed in ~S: ~S"
-                         :format-arguments (list name case))
+                  (progn
+                    ;; FIXME: this message could probably do with
+                    ;; some loving pretty-printer format controls.
+                    (style-warn "Treating bare ~A in ~A as introducing a normal-clause, not an otherwise-clause" keyoid name)
+                    (push keyoid keys)
+                    (push `((,test ,keyform-value ',keyoid) nil ,@forms)
+                          clauses))

                   (push `(t nil ,@forms) clauses)))
              ((and multi-p (listp keyoid))
               (setf keys (append keyoid keys))
                   (push `(t nil ,@forms) clauses)))
              ((and multi-p (listp keyoid))
               (setf keys (append keyoid keys))

@@ -259,7 +232,7 @@
         (cond
          ,@(nreverse clauses)
          ,@(if errorp
         (cond
          ,@(nreverse clauses)
          ,@(if errorp

-               `((t (error 'sb!conditions::case-failure
+               `((t (error 'case-failure

                            :name ',name
                            :datum ,keyform-value
                            :expected-type ',expected-type
                            :name ',name
                            :datum ,keyform-value
                            :expected-type ',expected-type

@@ -376,7 +349,7 @@
 
 (defmacro-mundanely nth-value (n form)
   #!+sb-doc
 
 (defmacro-mundanely nth-value (n form)
   #!+sb-doc

-  "Evaluates FORM and returns the Nth value (zero based). This involves no
+  "Evaluate FORM and return the Nth value (zero based). This involves no

   consing when N is a trivial constant integer."
   (if (integerp n)
       (let ((dummy-list nil)
   consing when N is a trivial constant integer."
   (if (integerp n)
       (let ((dummy-list nil)

@@ -400,29 +373,23 @@
   #!+sb-doc
   "DECLAIM Declaration*
   Do a declaration or declarations for the global environment."
   #!+sb-doc
   "DECLAIM Declaration*
   Do a declaration or declarations for the global environment."

-  #-sb-xc-host

   `(eval-when (:compile-toplevel :load-toplevel :execute)
   `(eval-when (:compile-toplevel :load-toplevel :execute)

-     ,@(mapcar #'(lambda (x)
-                  `(sb!xc:proclaim ',x))
-              specs))
-  ;; KLUDGE: The definition above doesn't work in the cross-compiler,
-  ;; because UNCROSS translates SB!XC:PROCLAIM into CL:PROCLAIM before
-  ;; the form gets executed. Instead, we have to explicitly do the
-  ;; proclamation at macroexpansion time. -- WHN ca. 19990810
-  ;;
-  ;; FIXME: Maybe we don't need this special treatment any more now
-  ;; that we're using DEFMACRO-MUNDANELY instead of DEFMACRO?
-  #+sb-xc-host (progn
-                (mapcar #'sb!xc:proclaim specs)
-                `(progn
-                   ,@(mapcar #'(lambda (x)
-                                 `(sb!xc:proclaim ',x))
-                             specs))))
+     ,@(mapcar (lambda (spec) `(sb!xc:proclaim ',spec))
+              specs)))

 
 

-(defmacro-mundanely print-unreadable-object ((object stream
-                                             &key type identity)
+(defmacro-mundanely print-unreadable-object ((object stream &key type identity)

                                             &body body)
                                             &body body)

+  "Output OBJECT to STREAM with \"#<\" prefix, \">\" suffix, optionally
+  with object-type prefix and object-identity suffix, and executing the
+  code in BODY to provide possible further output."

   `(%print-unreadable-object ,object ,stream ,type ,identity
                             ,(if body
   `(%print-unreadable-object ,object ,stream ,type ,identity
                             ,(if body

-                                 `#'(lambda () ,@body)
+                                 `(lambda () ,@body)

                                  nil)))
                                  nil)))

+
+(defmacro-mundanely ignore-errors (&rest forms)
+  #!+sb-doc
+  "Execute FORMS handling ERROR conditions, returning the result of the last
+  form, or (VALUES NIL the-ERROR-that-was-caught) if an ERROR was handled."
+  `(handler-case (progn ,@forms)
+     (error (condition) (values nil condition))))