An actual running implementation, which makes code that compiles.
[sod] / src / module-parse.lisp
index 6fb6be8..df4ea27 100644 (file)
 ;;;--------------------------------------------------------------------------
 ;;; Toplevel syntax.
 
-(export 'module)
-
 ;;; Type names.
 
-(define-pluggable-parser module typename (scanner)
-  ;; `typename' ID ( `,' ID )* `;'
-
+(define-pluggable-parser module typename (scanner pset)
+  ;; `typename' id ( `,' id )* `;'
+  (declare (ignore pset))
   (with-parser-context (token-scanner-context :scanner scanner)
     (parse (and "typename"
                (skip-many (:min 1)
 
 ;;; Fragments.
 
-(define-pluggable-parser module code (scanner)
-  ;; `code' ID `:' ID [ CONSTRAINTS ] `{' C-FRAGMENT `}'
-
+(define-pluggable-parser module code (scanner pset)
+  ;; `code' id `:' id [constraints] `{' c-fragment `}'
+  ;;
+  ;; constrains ::= `[' constraint-list `]'
+  ;; constraint ::= id+
+  (declare (ignore pset))
   (with-parser-context (token-scanner-context :scanner scanner)
-    (parse (seq ("code"
-                (reason :id)
-                #\:
-                (name :id)
-                (constraints (? (seq (#\[
-                                      (constraints (list (:min 1)
-                                                     (list (:min 1) :id)
-                                                     #\,))
-                                      #\])
-                                  constraints)))
-                (fragment (parse-delimited-fragment scanner #\{ #\})))
-            (add-to-module *module* (make-instance 'code-fragment-item
-                                                   :fragment fragment
-                                                   :constraints constraints
-                                                   :reason reason
-                                                   :name name))))))
+    (flet ((kw ()
+            (parse (seq ((kw :id)) (intern (string-upcase kw) 'keyword)))))
+      (parse (seq ("code"
+                  (reason (kw))
+                  #\:
+                  (name (kw))
+                  (constraints (? (seq (#\[
+                                        (constraints (list (:min 1)
+                                                       (list (:min 1) (kw))
+                                                       #\,))
+                                        #\])
+                                    constraints)))
+                  (fragment (parse-delimited-fragment scanner #\{ #\})))
+              (add-to-module *module*
+                             (make-instance 'code-fragment-item
+                                            :fragment fragment
+                                            :constraints constraints
+                                            :reason reason
+                                            :name name)))))))
 
 ;;; External files.
 
-(defun read-module (pathname &key (truename (truename pathname)) location)
+(export 'read-module)
+(defun read-module (pathname &key (truename nil truep) location)
   "Parse the file at PATHNAME as a module, returning it.
 
    This is the main entry point for parsing module files.  You may well know
@@ -83,6 +88,9 @@
    `file-location' object, though it might be anything other than `t' which
    can be printed in the event of circular imports."
 
+  (setf pathname (merge-pathnames pathname
+                                 (make-pathname :type "SOD" :case :common)))
+  (unless truep (setf truename (truename pathname)))
   (define-module (pathname :location location :truename truename)
     (with-open-file (f-stream pathname :direction :input)
       (let* ((*readtable* (copy-readtable))
                                     :char-scanner char-scanner)))
        (with-default-error-location (scanner)
          (with-parser-context (token-scanner-context :scanner scanner)
-           (parse (skip-many () (plug module scanner)))))))))
-
-(define-pluggable-parser module test (scanner)
-  ;; `demo' STRING `;'
-
+           (parse (skip-many ()
+                    (seq ((pset (parse-property-set scanner))
+                          (nil (error ()
+                                 (plug module scanner pset))))
+                      (check-unused-properties pset))))))))))
+
+(define-pluggable-parser module test (scanner pset)
+  ;; `demo' string `;'
+  (declare (ignore pset))
   (with-parser-context (token-scanner-context :scanner scanner)
     (parse (seq ("demo" (string :string) #\;)
             (format t ";; DEMO ~S~%" string)))))
 
-(define-pluggable-parser module file (scanner)
-  ;; `import' STRING `;'
-  ;; `load' STRING `;'
-
+(define-pluggable-parser module file (scanner pset)
+  ;; `import' string `;'
+  ;; `load' string `;'
+  (declare (ignore pset))
   (flet ((common (name type what thunk)
           (find-file scanner
                      (merge-pathnames name
 
 ;;; Lisp escape.
 
-(define-pluggable-parser module lisp (scanner)
+(define-pluggable-parser module lisp (scanner pset)
   ;; `lisp' s-expression `;'
-
+  (declare (ignore pset))
   (with-parser-context (token-scanner-context :scanner scanner)
     (parse (seq ((sexp (if (and (eql (token-type scanner) :id)
                                (string= (token-value scanner) "lisp"))
 ;;;--------------------------------------------------------------------------
 ;;; Class declarations.
 
-(defun parse-class-body (scaner pset name supers)
+(defun parse-class-body (scanner pset name supers)
   ;; class-body ::= `{' class-item* `}'
+  ;;
+  ;; class-item ::= property-set raw-class-item
   (with-parser-context (token-scanner-context :scanner scanner)
     (make-class-type name)
-    (let* ((class (make-sod-class name (mapcat #'find-sod-class supers)
+    (let* ((class (make-sod-class name (mapcar #'find-sod-class supers)
                                  pset scanner))
           (nick (sod-class-nickname class)))
 
                 ;; names.
                 (parse-declarator
                  scanner base-type
-                 :centre (parser ()
+                 :kernel (parser ()
                            (seq ((name-a :id)
                                  (name-b (? (seq (#\. (id :id)) id))))
                              (if name-b (cons name-a name-b)
                                  name-a)))))
 
-              ;; class-item ::= [property-set] raw-class-item
-              ;;
-
               (parse-message-item (sub-pset type name)
                 ;; message-item ::=
                 ;;     declspec+ declarator -!- (method-body | `;')
                 (make-sod-message class name type sub-pset scanner)
-                (parse (or #\; (parse-method-item nil type nick name))))
+                (parse (or #\; (parse-method-item sub-pset
+                                                  type nick name))))
 
               (parse-method-item (sub-pset type sub-nick name)
                 ;; method-item ::=
                 ;;
                 ;; Return (VALUE-KIND . VALUE-FORM), ready for passing to a
                 ;; `sod-initializer' constructor.
-                (parse (or (peek (seq (#\= (frag (parse-delimited-fragment
-                                                  scanner #\{ #\})))
-                                   (cons :compound frag)))
-                           (seq ((frag (parse-delimited-fragment
-                                        scanner #\= '(#\; #\,)
-                                        :keep-end t)))
-                             (cons :simple frag)))))
+
+                ;; This is kind of tricky because we have to juggle both
+                ;; layers of the parsing machinery.  The character scanner
+                ;; will already have consumed the lookahead token (which, if
+                ;; we're going to do anything, is `=').
+                (let ((char-scanner (token-scanner-char-scanner scanner)))
+
+                  ;; First, skip the character-scanner past any whitespace.
+                  ;; We don't record this consumption, which is a bit
+                  ;; naughty, but nobody will actually mind.
+                  (loop
+                    (when (or (scanner-at-eof-p char-scanner)
+                              (not (whitespace-char-p
+                                    (scanner-current-char char-scanner))))
+                      (return))
+                    (scanner-step char-scanner))
+
+                  ;; Now maybe read an initializer.
+                  (cond ((not (eql (token-type scanner) #\=))
+                         ;; It's not an `=' after all.  There's no
+                         ;; initializer.
+                         (values '(#\=) nil nil))
+
+                        ((and (not (scanner-at-eof-p char-scanner))
+                              (char= (scanner-current-char char-scanner)
+                                     #\{))
+                         ;; There's a brace after the `=', so we should
+                         ;; consume the `=' here, and read a compound
+                         ;; initializer enclosed in braces.
+                         (parse (seq (#\= (frag (parse-delimited-fragment
+                                                 scanner #\{ #\})))
+                                  (cons :compound frag))))
+
+                        (t
+                         ;; No brace, so read from the `=' up to, but not
+                         ;; including, the trailing `,' or `;' delimiter.
+                         (parse (seq ((frag (parse-delimited-fragment
+                                             scanner #\= '(#\; #\,)
+                                             :keep-end t)))
+                                  (cons :simple frag)))))))
 
               (parse-slot-item (sub-pset base-type type name)
                 ;; slot-item ::=
                               (when init
                                 (make-sod-instance-initializer
                                  class nick name (car init) (cdr init)
-                                 nil scanner)))
+                                 sub-pset scanner)))
                             (skip-many ()
                               (seq (#\,
                                     (ds (parse-declarator scanner
                                   (make-sod-instance-initializer
                                    class nick (cdr ds)
                                    (car init) (cdr init)
-                                   nil scanner))))
+                                   sub-pset scanner))))
                             #\;)))
 
               (parse-initializer-item (sub-pset constructor)
                 ;; Most of the above begin with declspecs and a declarator
                 ;; (which might be dotted).  So we parse that here and
                 ;; dispatch based on what we find.
-                (parse (or (peek
+                (parse (or (plug class-item scanner class sub-pset)
+                           ;(peek
                             (seq ((ds (parse-c-type scanner))
                                   (dc (parse-maybe-dotted-declarator ds))
-                                  (result (class-item-dispatch sub-pset
-                                                               ds
-                                                               (car dc)
-                                                               (cdr dc))))
-                              result))
+                                  (nil (class-item-dispatch sub-pset
+                                                            ds
+                                                            (car dc)
+                                                            (cdr dc)))));)
                            (and "class"
                                 (parse-initializer-item
                                  sub-pset
                             sub-pset
                             #'make-sod-instance-initializer)))))
 
-       (parse (and #\{
-                   (skip-many ()
-                     (seq ((sub-pset (? (parse-property-set)))
-                           (nil (parse-raw-class-item sub-pset)))))
-                   #\}))))))
+       (parse (seq (#\{
+                    (nil (skip-many ()
+                           (seq ((sub-pset (parse-property-set scanner))
+                                 (nil (parse-raw-class-item sub-pset)))
+                             (check-unused-properties sub-pset))))
+                    (nil (error () #\})))
+                (finalize-sod-class class)
+                (add-to-module *module* class)))))))
 
-(define-pluggable-parser module class (scanner)
+(define-pluggable-parser module class (scanner pset)
   ;; `class' id [`:' id-list] class-body
   ;; `class' id `;'
-
   (with-parser-context (token-scanner-context :scanner scanner)
     (parse (seq ("class"
                 (name :id)
                                      scanner
                                      pset name supers)))))))))))
 
-
-
-
-    (parse (seq ("class"
-                (name :id)
-                (supers (? (seq (#\: (supers (list (:min 1) :id #\,)))
-                                supers)))
-                #\{
-                
-
 ;;;----- That's all, folks --------------------------------------------------