1 ;;;; This software is part of the SBCL system. See the README file for
4 ;;;; This software is derived from the CMU CL system, which was
5 ;;;; written at Carnegie Mellon University and released into the
6 ;;;; public domain. The software is in the public domain and is
7 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
8 ;;;; files for more information.
12 (/show0 "parse-lambda-list.lisp 12")
14 ;;; Break something like a lambda list (but not necessarily actually a
15 ;;; lambda list, e.g. the representation of argument types which is
16 ;;; used within an FTYPE specification) into its component parts. We
17 ;;; return twelve values:
18 ;;; 1. a list of the required args;
19 ;;; 2. a list of the &OPTIONAL arg specs;
20 ;;; 3. true if a &REST arg was specified;
22 ;;; 5. true if &KEY args are present;
23 ;;; 6. a list of the &KEY arg specs;
24 ;;; 7. true if &ALLOW-OTHER-KEYS was specified.;
25 ;;; 8. true if any &AUX is present (new in SBCL vs. CMU CL);
26 ;;; 9. a list of the &AUX specifiers;
27 ;;; 10. true if a &MORE arg was specified;
28 ;;; 11. the &MORE context var;
29 ;;; 12. the &MORE count var;
30 ;;; 13. true if any lambda list keyword is present (only for
31 ;;; PARSE-LAMBDA-LIST-LIKE-THING).
33 ;;; The top level lambda list syntax is checked for validity, but the
34 ;;; arg specifiers are just passed through untouched. If something is
35 ;;; wrong, we use COMPILER-ERROR, aborting compilation to the last
37 (declaim (ftype (sfunction (list)
38 (values list list boolean t boolean list boolean
39 boolean list boolean t t boolean))
40 parse-lambda-list-like-thing))
41 (declaim (ftype (sfunction (list)
42 (values list list boolean t boolean list boolean
43 boolean list boolean t t))
45 (defun parse-lambda-list-like-thing (list)
59 (declare (type (member :allow-other-keys :aux
61 :more-context :more-count
67 (if (member arg sb!xc:lambda-list-keywords)
70 (unless (eq state :required)
71 (compiler-error "misplaced &OPTIONAL in lambda list: ~S"
73 (setq state :optional))
75 (unless (member state '(:required :optional))
76 (compiler-error "misplaced &REST in lambda list: ~S" list))
79 (unless (member state '(:required :optional))
80 (compiler-error "misplaced &MORE in lambda list: ~S" list))
85 '(:required :optional :post-rest :post-more))
86 (compiler-error "misplaced &KEY in lambda list: ~S" list))
90 "&OPTIONAL and &KEY found in the same lambda list: ~S" list))
94 (unless (eq state ':key)
95 (compiler-error "misplaced &ALLOW-OTHER-KEYS in ~
99 state :allow-other-keys))
101 (when (member state '(:rest :more-context :more-count))
102 (compiler-error "misplaced &AUX in lambda list: ~S" list))
104 (compiler-error "multiple &AUX in lambda list: ~S" list))
108 ;; It could be argued that &WHOLE and friends would be
109 ;; just ordinary variables in an ordinary lambda-list,
110 ;; but since (1) that seem exceedingly to have been the
111 ;; programmers intent and (2) the spec can be
112 ;; interpreted as giving as licence to signal an
113 ;; error[*] that is what we do.
115 ;; [* All lambda list keywords used in the
116 ;; implementation appear in LAMBDA-LIST-KEYWORDS. Each
117 ;; member of a lambda list is either a parameter
118 ;; specifier ot a lambda list keyword. Ergo, symbols
119 ;; appearing in LAMBDA-LIST-KEYWORDS cannot be
120 ;; parameter specifiers.]
121 (compiler-error 'simple-program-error
122 :format-control "Bad lambda list keyword ~S in: ~S"
123 :format-arguments (list arg list))))
126 (let ((name (symbol-name arg)))
127 (when (and (plusp (length name))
128 (char= (char name 0) #\&))
130 "suspicious variable in lambda list: ~S." arg))))
132 (:required (required arg))
133 (:optional (optional arg))
139 (setq more-context arg
147 (compiler-error "found garbage in lambda list when expecting ~
150 (when (eq state :rest)
151 (compiler-error "&REST without rest variable"))
153 (values (required) (optional) restp rest keyp (keys) allowp auxp (aux)
154 morep more-context more-count
155 (neq state :required)))))
157 ;;; like PARSE-LAMBDA-LIST-LIKE-THING, except our LAMBDA-LIST argument
158 ;;; really *is* a lambda list, not just a "lambda-list-like thing", so
159 ;;; can barf on things which're illegal as arguments in lambda lists
160 ;;; even if they could conceivably be legal in not-quite-a-lambda-list
162 (defun parse-lambda-list (lambda-list)
163 ;; Classify parameters without checking their validity individually.
164 (multiple-value-bind (required optional restp rest keyp keys allowp auxp aux
165 morep more-context more-count)
166 (parse-lambda-list-like-thing lambda-list)
168 ;; Check validity of parameters.
169 (flet ((need-symbol (x why)
171 (compiler-error "~A is not a symbol: ~S" why x))))
173 (need-symbol i "Required argument"))
178 (destructuring-bind (var &optional init-form supplied-p) i
179 (declare (ignore init-form supplied-p))
180 (need-symbol var "&OPTIONAL parameter name")))
182 (compiler-error "&OPTIONAL parameter is not a symbol or cons: ~S"
185 (need-symbol rest "&REST argument"))
191 (destructuring-bind (var-or-kv &optional init-form supplied-p) i
192 (declare (ignore init-form supplied-p))
193 (if (consp var-or-kv)
194 (destructuring-bind (keyword-name var) var-or-kv
195 (declare (ignore keyword-name))
196 (need-symbol var "&KEY parameter name"))
197 (need-symbol var-or-kv "&KEY parameter name"))))
199 (compiler-error "&KEY parameter is not a symbol or cons: ~S"
203 (values required optional restp rest keyp keys allowp auxp aux
204 morep more-context more-count)))
206 (/show0 "parse-lambda-list.lisp end of file")