Fixes bug 181105: syntax pattern variable list length mismatch error

is obscure

scheme/last-revision

@@ -1 +1 @@
-1334
+1335

scheme/makefile.ss

@@ -1382,6 +1382,7 @@
     [make-i/o-would-block-condition   i]
     [i/o-would-block-condition?       i]
     [i/o-would-block-port             i]
+    [ellipsis-map ]
   ))
 
 (define (macro-identifier? x) 

scheme/psyntax.expander.ss

@@ -25,7 +25,7 @@
           syntax-violation
           syntax->datum make-variable-transformer
           eval-r6rs-top-level boot-library-expand eval-top-level
-          null-environment scheme-report-environment)
+          null-environment scheme-report-environment ellipsis-map)
   (import
     (except (rnrs) 
       environment environment? identifier?
@@ -2226,6 +2226,21 @@
                    (build-lambda no-source (list x) body)
                    (list (chi-expr expr r mr)))))))))))
 
+  (define (ellipsis-map proc ls . ls*)
+    (define who '...)
+    (unless (list? ls) 
+      (assertion-violation who "not a list" ls))
+    (unless (null? ls*)
+      (let ([n (length ls)])
+        (for-each
+          (lambda (x) 
+            (unless (list? x) 
+              (assertion-violation who "not a list" x))
+            (unless (= (length x) n)
+              (assertion-violation who "length mismatch" ls x)))
+          ls*)))
+    (apply map proc ls ls*))
+
   (define syntax-transformer
     (let ()
       (define gen-syntax
@@ -2358,7 +2373,7 @@
             ((map)
              (let ((ls (map regen (cdr x))))
                (build-application no-source
-                   (build-primref no-source 'map)
+                 (build-primref no-source 'ellipsis-map)
                  ls)))
             (else
              (build-application no-source