- interface between write/display and custom struct writers is

changed in order to allow large structures (e.g., libraries,
  syntax objects, etc.) to print efficiently.  This is done by only
  traversing the parts of the structure that will actually be
  printed, rather than traversing the whole data structure (which is
  what write/display used to do).  Pretty-print should be fixed in a
  similar manner (TODO).

scheme/ikarus.records.procedural.ss

@@ -447,11 +447,11 @@
         (car (vector-ref (rtd-fields rtd) k)))))
 
   (set-rtd-printer! (type-descriptor rtd)
-    (lambda (x p) 
+    (lambda (x p wr) 
       (display (format "#<record-type-descriptor ~s>" (rtd-name x)) p)))
 
   (set-rtd-printer! (type-descriptor rcd)
-    (lambda (x p) 
+    (lambda (x p wr) 
       (display (format "#<record-constructor-descriptor ~s>"
                        (rtd-name (rcd-rtd x))) p)))
                   

scheme/ikarus.structs.ss

@@ -279,7 +279,7 @@
   (set-rtd-fields! (base-rtd) '(name fields length printer symbol))
   (set-rtd-name! (base-rtd) "base-rtd")
   ($set-rtd-printer! (base-rtd)
-    (lambda (x p)
+    (lambda (x p wr)
       (unless (rtd? x)
         (die 'struct-type-printer "not an rtd"))
       (display "#<" p)

scheme/last-revision

@@ -1 +1 @@
-1626
+1627

scheme/psyntax.expander.ss

@@ -261,7 +261,7 @@
 
   ;;; Now to syntax objects which are records defined like:
   (define-record stx (expr mark* subst* ae*)
-    (lambda (x p)
+    (lambda (x p wr)
       (display "#<syntax " p)
       (write (stx->datum x) p)
       (let ((expr (stx-expr x)))
@@ -3581,11 +3581,11 @@
   ;;; An env record encapsulates a substitution and a set of
   ;;; libraries.
   (define-record env (names labels itc)
-    (lambda (x p)
+    (lambda (x p wr)
       (display "#<environment>" p)))
 
   (define-record interaction-env (rib r locs)
-    (lambda (x p)
+    (lambda (x p wr)
       (display "#<environment>" p)))
   
   (define environment?

scheme/psyntax.library-manager.ss

@@ -52,7 +52,7 @@
     (id name version imp* vis* inv* subst env visit-state
         invoke-state visit-code invoke-code visible?
         source-file-name)
-    (lambda (x p)
+    (lambda (x p wr)
       (unless (library? x)
         (assertion-violation 'record-type-printer "not a library"))
       (display