+;;;; EVAL and friends
+
;;;; This software is part of the SBCL system. See the README file for
;;;; more information.
;;;;
;;;; provided with absolutely no warranty. See the COPYING and CREDITS
;;;; files for more information.
-(in-package "SB!BYTECODE")
-
-;;; This is defined here so that the printer etc. can call
-;;; INTERPRETED-FUNCTION-P before the full interpreter is loaded.
-
-;;; an interpreted function
-(defstruct (interpreted-function
- (:alternate-metaclass sb!kernel:funcallable-instance
- sb!kernel:funcallable-structure-class
- sb!kernel:make-funcallable-structure-class)
- (:type sb!kernel:funcallable-structure)
- (:constructor %make-interpreted-function)
- (:copier nil)
- ;; FIXME: Binding PRINT-OBJECT isn't going to help unless
- ;; we fix the print-a-funcallable-instance code so that
- ;; it calls PRINT-OBJECT in this case.
- (:print-object
- (lambda (x stream)
- (print-unreadable-object (x stream :identity t)
- (interpreted-function-%name x)))))
- ;; The name of this interpreted function, or NIL if none specified.
- (%name nil)
- ;; This function's debug arglist.
- (arglist nil)
- ;; A lambda that can be converted to get the definition.
- (lambda nil)
- ;; If this function has been converted, then this is the XEP. If this is
- ;; false, then the function is not in the cache (or is in the process of
- ;; being removed.)
- (definition nil :type (or sb!c::clambda null))
- ;; The number of consecutive GCs that this function has been unused.
- ;; This is used to control cache replacement.
- (gcs 0 :type sb!c::index)
- ;; True if Lambda has been converted at least once, and thus warnings should
- ;; be suppressed on additional conversions.
- (converted-once nil)
- ;; For a closure, the closure date vector.
- (closure nil :type (or null simple-vector)))
-\f
-;;; FIXME: Could we make this extra IN-PACKAGE go away, so that all
-;;; this bytecode interpreter implementation stuff was in the
-;;; SB!BYTECODE package?
(in-package "SB!IMPL")
-;;;; EVAL and friends
-
-;;; This needs to be initialized in the cold load, since the top-level
-;;; catcher will always restore the initial value.
-(defvar *eval-stack-top* 0)
-
;;; general case of EVAL (except in that it can't handle toplevel
-;;; EVAL-WHEN magic properly): Delegate to the byte compiler.
-(defun sb!bytecode:internal-eval (expr)
- (funcall (compile (gensym "EVAL-TMPFUN-")
- `(lambda ()
-
- ;; SPEED=0,DEBUG=1 => byte-compile
- (declare (optimize (speed 0) (debug 1)))
-
- ;; Other than that, basically we care about
- ;; compilation speed, compilation speed, and
- ;; compilation speed. (There are cases where
- ;; the user wants something else, but we don't
- ;; know enough to guess that; and if he is
- ;; unhappy about our guessed emphasis, he
- ;; should explicitly compile his code, with
- ;; explicit declarations to tell us what to
- ;; emphasize.)
- (declare (optimize (space 1) (safety 1)))
- (declare (optimize (compilation-speed 3)))
-
- ,expr))))
+;;; EVAL-WHEN magic properly): Delegate to #'COMPILE.
+(defun %eval (expr lexenv)
+ (funcall (sb!c:compile-in-lexenv
+ (gensym "EVAL-TMPFUN-")
+ `(lambda ()
+ ,expr)
+ lexenv)))
+
+;;; Handle PROGN and implicit PROGN.
+(defun eval-progn-body (progn-body lexenv)
+ (unless (list-with-length-p progn-body)
+ (let ((*print-circle* t))
+ (error 'simple-program-error
+ :format-control
+ "~@<not a proper list in PROGN or implicit PROGN: ~2I~_~S~:>"
+ :format-arguments (list progn-body))))
+ ;; Note:
+ ;; * We can't just use (MAP NIL #'EVAL PROGN-BODY) here, because we
+ ;; need to take care to return all the values of the final EVAL.
+ ;; * It's left as an exercise to the reader to verify that this
+ ;; gives the right result when PROGN-BODY is NIL, because
+ ;; (FIRST NIL) = (REST NIL) = NIL.
+ (do* ((i progn-body rest-i)
+ (rest-i (rest i) (rest i)))
+ (nil)
+ (if rest-i ; if not last element of list
+ (eval-in-lexenv (first i) lexenv)
+ (return (eval-in-lexenv (first i) lexenv)))))
-;;; Pick off a few easy cases, and call INTERNAL-EVAL for the rest. If
-;;; *ALREADY-EVALED-THIS* is true, then we bind it to NIL before doing
-;;; a call so that the effect is confined to the lexical scope of the
-;;; EVAL-WHEN.
(defun eval (original-exp)
#!+sb-doc
"Evaluate the argument in a null lexical environment, returning the
result or results."
+ (eval-in-lexenv original-exp (make-null-lexenv)))
+
+;;; Pick off a few easy cases, and the various top level EVAL-WHEN
+;;; magical cases, and call %EVAL for the rest.
+(defun eval-in-lexenv (original-exp lexenv)
(declare (optimize (safety 1)))
- (let ((exp (macroexpand original-exp)))
+ ;; (aver (lexenv-simple-p lexenv))
+ (let ((exp (macroexpand original-exp lexenv)))
(typecase exp
(symbol
(ecase (info :variable :kind exp)
(values (info :variable :constant-value exp)))
((:special :global)
(symbol-value exp))
+ ;; FIXME: This special case here is a symptom of non-ANSI
+ ;; weirdness in SBCL's ALIEN implementation, which could
+ ;; cause problems for e.g. code walkers. It'd probably be
+ ;; good to ANSIfy it by making alien variable accessors into
+ ;; ordinary forms, e.g. (SB-UNIX:ENV) and (SETF SB-UNIX:ENV),
+ ;; instead of magical symbols, e.g. plain SB-UNIX:ENV. Then
+ ;; if the old magical-symbol syntax is to be retained for
+ ;; compatibility, it can be implemented with
+ ;; DEFINE-SYMBOL-MACRO, keeping the code walkers happy.
(:alien
- (sb!bytecode:internal-eval original-exp))))
+ (%eval original-exp lexenv))))
(list
(let ((name (first exp))
- (args (1- (length exp))))
+ (n-args (1- (length exp))))
(case name
- (function
- (unless (= args 1)
+ ((function)
+ (unless (= n-args 1)
(error "wrong number of args to FUNCTION:~% ~S" exp))
(let ((name (second exp)))
- (if (or (atom name)
- (and (consp name)
- (eq (car name) 'setf)))
+ (if (and (or (atom name)
+ (and (consp name)
+ (eq (car name) 'setf)))
+ (not (consp (let ((sb!c:*lexenv* lexenv))
+ (sb!c:lexenv-find name funs)))))
(fdefinition name)
- (sb!bytecode:internal-eval original-exp))))
- (quote
- (unless (= args 1)
+ (%eval original-exp lexenv))))
+ ((quote)
+ (unless (= n-args 1)
(error "wrong number of args to QUOTE:~% ~S" exp))
(second exp))
(setq
- (unless (evenp args)
+ (unless (evenp n-args)
(error "odd number of args to SETQ:~% ~S" exp))
- (unless (zerop args)
+ (unless (zerop n-args)
(do ((name (cdr exp) (cddr name)))
((null name)
(do ((args (cdr exp) (cddr args)))
(set (first args) (eval (second args)))))
(let ((symbol (first name)))
(case (info :variable :kind symbol)
- ;; FIXME: I took out the *TOP-LEVEL-AUTO-DECLARE*
- ;; test here, and removed the *TOP-LEVEL-AUTO-DECLARE*
+ ;; FIXME: I took out the *TOPLEVEL-AUTO-DECLARE*
+ ;; test here, and removed the *TOPLEVEL-AUTO-DECLARE*
;; variable; the code should now act as though that
;; variable is NIL. This should be tested..
(:special)
- (t (return (sb!bytecode:internal-eval original-exp))))))))
+ (t (return (%eval original-exp lexenv))))))))
((progn)
- (when (> args 0)
- (dolist (x (butlast (rest exp)) (eval (car (last exp))))
- (eval x))))
+ (eval-progn-body (rest exp) lexenv))
((eval-when)
- (if (and (> args 0)
- (or (member 'eval (second exp))
- (member :execute (second exp))))
- (when (> args 1)
- (dolist (x (butlast (cddr exp)) (eval (car (last exp))))
- (eval x)))
- (sb!bytecode:internal-eval original-exp)))
+ ;; FIXME: DESTRUCTURING-BIND returns ARG-COUNT-ERROR
+ ;; instead of PROGRAM-ERROR when there's something wrong
+ ;; with the syntax here (e.g. missing SITUATIONS). This
+ ;; could be fixed by hand-crafting clauses to catch and
+ ;; report each possibility, but it would probably be
+ ;; cleaner to write a new macro
+ ;; DESTRUCTURING-BIND-PROGRAM-SYNTAX which does
+ ;; DESTRUCTURING-BIND and promotes any mismatch to
+ ;; PROGRAM-ERROR, then to use it here and in (probably
+ ;; dozens of) other places where the same problem arises.
+ (destructuring-bind (eval-when situations &rest body) exp
+ (declare (ignore eval-when))
+ (multiple-value-bind (ct lt e)
+ (sb!c:parse-eval-when-situations situations)
+ ;; CLHS 3.8 - Special Operator EVAL-WHEN: The use of
+ ;; the situation :EXECUTE (or EVAL) controls whether
+ ;; evaluation occurs for other EVAL-WHEN forms; that
+ ;; is, those that are not top level forms, or those in
+ ;; code processed by EVAL or COMPILE. If the :EXECUTE
+ ;; situation is specified in such a form, then the
+ ;; body forms are processed as an implicit PROGN;
+ ;; otherwise, the EVAL-WHEN form returns NIL.
+ (declare (ignore ct lt))
+ (when e
+ (eval-progn-body body lexenv)))))
+ ((locally)
+ (multiple-value-bind (body decls) (parse-body (rest exp) nil)
+ (let ((lexenv
+ ;; KLUDGE: Uh, yeah. I'm not anticipating
+ ;; winning any prizes for this code, which was
+ ;; written on a "let's get it to work" basis.
+ ;; These seem to be the variables that need
+ ;; bindings for PROCESS-DECLS to work
+ ;; (*FREE-FUNS* and *FREE-VARS* so that
+ ;; references to free functions and variables in
+ ;; the declarations can be noted;
+ ;; *UNDEFINED-WARNINGS* so that warnings about
+ ;; undefined things can be accumulated [and then
+ ;; thrown away, as it happens]). -- CSR, 2002-10-24
+ (let ((sb!c:*lexenv* lexenv)
+ (sb!c::*free-funs* (make-hash-table :test 'equal))
+ (sb!c::*free-vars* (make-hash-table :test 'eq))
+ (sb!c::*undefined-warnings* nil))
+ (sb!c::process-decls decls
+ nil nil
+ (sb!c::make-continuation)
+ lexenv))))
+ (eval-progn-body body lexenv))))
+ ((macrolet)
+ (destructuring-bind (definitions &rest body)
+ (rest exp)
+ ;; FIXME: shared code with FUNCALL-IN-FOOMACROLET-LEXENV
+ (declare (type list definitions))
+ (unless (= (length definitions)
+ (length (remove-duplicates definitions :key #'first)))
+ (style-warn "duplicate definitions in ~S" definitions))
+ (let ((lexenv
+ (sb!c::make-lexenv
+ :default lexenv
+ :funs (mapcar
+ (sb!c::macrolet-definitionize-fun
+ :eval
+ ;; I'm not sure that this is the correct
+ ;; LEXENV to be compiling local macros
+ ;; in...
+ lexenv)
+ definitions))))
+ (eval-in-lexenv `(locally ,@body) lexenv))))
+ ((symbol-macrolet)
+ (destructuring-bind (definitions &rest body)
+ (rest exp)
+ ;; FIXME: shared code with FUNCALL-IN-FOOMACROLET-LEXENV
+ (declare (type list definitions))
+ (unless (= (length definitions)
+ (length (remove-duplicates definitions :key #'first)))
+ (style-warn "duplicate definitions in ~S" definitions))
+ (let ((lexenv
+ (sb!c::make-lexenv
+ :default lexenv
+ :vars (mapcar
+ (sb!c::symbol-macrolet-definitionize-fun
+ :eval)
+ definitions))))
+ (eval-in-lexenv `(locally ,@body) lexenv))))
(t
(if (and (symbolp name)
(eq (info :function :kind name) :function))
(collect ((args))
- (dolist (arg (rest exp))
- (args (eval arg)))
- (apply (symbol-function name) (args)))
- (sb!bytecode:internal-eval original-exp))))))
+ (dolist (arg (rest exp))
+ (args (eval-in-lexenv arg lexenv)))
+ (apply (symbol-function name) (args)))
+ (%eval exp lexenv))))))
(t
exp))))
-
-;;; Given a function, return three values:
-;;; 1] A lambda expression that could be used to define the function,
-;;; or NIL if the definition isn't available.
-;;; 2] NIL if the function was definitely defined in a null lexical
-;;; environment, and T otherwise.
-;;; 3] Some object that \"names\" the function. Although this is
-;;; allowed to be any object, CMU CL always returns a valid
-;;; function name or a string.
-;;;
-;;; If interpreted, use the interpreter interface. Otherwise, see
-;;; whether it was compiled with COMPILE. If that fails, check for an
-;;; inline expansion.
-(defun function-lambda-expression (fun)
- (declare (type function fun))
- (let* ((fun (%function-self fun))
- (name (%function-name fun))
- (code (sb!di::function-code-header fun))
- (info (sb!kernel:%code-debug-info code)))
- (if info
- (let ((source (first (sb!c::compiled-debug-info-source info))))
- (cond ((and (eq (sb!c::debug-source-from source) :lisp)
- (eq (sb!c::debug-source-info source) fun))
- (values (second (svref (sb!c::debug-source-name source) 0))
- nil name))
- ((stringp name)
- (values nil t name))
- (t
- (let ((exp (info :function :inline-expansion name)))
- (if exp
- (values exp nil name)
- (values nil t name))))))
- (values nil t name))))
-
-;;; This is like FIND-IF, except that we do it on a compiled closure's
-;;; environment.
-(defun find-if-in-closure (test fun)
- (dotimes (index (1- (get-closure-length fun)))
- (let ((elt (%closure-index-ref fun index)))
- (when (funcall test elt)
- (return elt)))))
\f
;;; miscellaneous full function definitions of things which are
;;; ordinarily handled magically by the compiler