Move datum->syntax back to init-7.scm. Don't crash when renamer not present in syntactic closure.

lib/chibi/syntax-case.scm

@@ -46,28 +46,6 @@
 (define (syntax->datum stx)
   (strip-syntactic-closures stx))
 
-(define (symbol->identifier id symbol)
-  (if (symbol? id)
-      symbol
-      ((syntactic-closure-rename id)
-       symbol)))
-
-;; TODO: Handle cycles in datum.
-(define (datum->syntax id datum)
-  (let loop ((datum datum))
-    (cond ((pair? datum)
-	   (cons (loop (car datum))
-		 (loop (cdr datum))))
-	  ((vector? datum)
-	   (do ((res (make-vector (vector-length datum)))
-		(i 0 (+ i 1)))
-	       ((= i (vector-length datum)) res)
-	     (vector-set! res i (loop (vector-ref datum i)))))
-	  ((symbol? datum)
-	   (symbol->identifier id datum))
-	  (else
-	   datum))))
-
 (define-syntax syntax (syntax-transformer #f))
 (define-syntax quasisyntax (syntax-transformer 0))
 (define-auxiliary-syntax unsyntax)

lib/init-7.scm

@@ -976,7 +976,7 @@
      (syntax-rules-transformer expr rename compare))))
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-;; let(rec)-syntax
+;; let(rec)-syntax and datum->syntax
 
 (define-syntax let-syntax
   (syntax-rules ()
@@ -988,6 +988,32 @@
     ((letrec-syntax ((keyword transformer) ...) . body)
      (%letrec-syntax ((keyword (make-transformer transformer)) ...) . body))))
 
+(define (symbol->identifier id symbol)
+  (cond
+   ((symbol? id)
+    symbol)
+   ((syntactic-closure-rename id)
+    => (lambda (renamer)
+	 (renamer symbol)))
+   (else
+    symbol)))
+
+;; TODO: Handle cycles in datum.
+(define (datum->syntax id datum)
+  (let loop ((datum datum))
+    (cond ((pair? datum)
+	   (cons (loop (car datum))
+		 (loop (cdr datum))))
+	  ((vector? datum)
+	   (do ((res (make-vector (vector-length datum)))
+		(i 0 (+ i 1)))
+	       ((= i (vector-length datum)) res)
+	     (vector-set! res i (loop (vector-ref datum i)))))
+	  ((symbol? datum)
+	   (symbol->identifier id datum))
+	  (else
+	   datum))))
+
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; additional syntax