fix varref' in compiler/zo-structs', etc.

and sync docs better with implementation

original commit: a4da2a3f4c

collects/compiler/decompile.rkt

@@ -195,7 +195,7 @@
   (match expr
     [(struct toplevel (depth pos const? ready?))
      (decompile-tl expr globs stack closed #f)]
-    [(struct varref (tl))
+    [(struct varref (tl dummy))
      `(#%variable-reference ,(decompile-tl tl globs stack closed #t))]
     [(struct topsyntax (depth pos midpt))
      (list-ref/protect (glob-desc-vars globs) (+ midpt pos) 'topsyntax)]

collects/compiler/demodularizer/gc-toplevels.rkt

@@ -120,8 +120,9 @@
       [(struct beg0 (seq))
        (for-each (lambda (f) (build-graph! lhs f))
                  seq)]
-      [(struct varref (tl))
+      [(struct varref (tl dummy))
-       (build-graph! lhs tl)]
+       (build-graph! lhs tl)
+       (build-graph! lhs dummy)]
       [(and f (struct assign (id rhs undef-ok?)))
        (build-graph! lhs id)
        (build-graph! lhs rhs)]
@@ -252,8 +253,8 @@
         (update body))]
       [(struct beg0 (seq))
        (make-beg0 (map update seq))]
-      [(struct varref (tl))
+      [(struct varref (tl dummy))
-       (make-varref (update tl))]
+       (make-varref (update tl) (update dummy))]
       [(and f (struct assign (id rhs undef-ok?)))
        (struct-copy assign f
                     [id (update id)]

collects/compiler/demodularizer/update-toplevels.rkt

@@ -68,8 +68,8 @@
         (update body))]
       [(struct beg0 (seq))
        (make-beg0 (map update seq))]
-      [(struct varref (tl))
+      [(struct varref (tl dummy))
-       (make-varref (update tl))]
+       (make-varref (update tl) (update dummy))]
       [(and f (struct assign (id rhs undef-ok?)))
        (struct-copy assign f
                     [id (update id)]

collects/compiler/zo-marshal.rkt

@@ -671,9 +671,9 @@
                         (protect-quote val)
                         (protect-quote body))
                        out)]
-       [(struct varref (expr))
+       [(struct varref (expr dummy))
         (out-marshaled varref-form-type-num
-                       expr
+                       (cons expr dummy)
                        out)]
        [(protected-symref v)
         (out-anything ((out-shared-index out) v #:error? #t) out)]

collects/compiler/zo-parse.rkt

@@ -207,7 +207,7 @@
 (define (read-require v)
   (make-req (cdr v) (car v)))
 (define (read-#%variable-ref v)
-  (make-varref v))
+  (make-varref (car v) (cdr v)))
 (define (read-apply-values v)
   (make-apply-values (car v) (cdr v)))
 (define (read-splice v)

collects/compiler/zo-structs.rkt

@@ -29,7 +29,7 @@
      [struct id ([field-id field-contract] ...)])))
 
 (define-struct zo () #:prefab)
-(provide zo?)
+(provide (struct-out zo))
 
 (define-syntax define-form-struct
   (syntax-rules ()
@@ -167,7 +167,7 @@
                                            [body (or/c expr? seq? any/c)])) ; `with-continuation-mark'
 (define-form-struct (beg0 expr) ([seq (listof (or/c expr? seq? any/c))])) ; `begin0'
 (define-form-struct (splice form) ([forms (listof (or/c form? any/c))])) ; top-level `begin'
-(define-form-struct (varref expr) ([toplevel toplevel?])) ; `#%variable-reference'
+(define-form-struct (varref expr) ([toplevel toplevel?] [dummy toplevel?])) ; `#%variable-reference'
 (define-form-struct (assign expr) ([id toplevel?] [rhs (or/c expr? seq? any/c)] [undef-ok? boolean?])) ; top-level or module-level set!
 (define-form-struct (apply-values expr) ([proc (or/c expr? seq? any/c)] [args-expr (or/c expr? seq? any/c)])) ; `(call-with-values (lambda () ,args-expr) ,proc)
 (define-form-struct (primval expr) ([id exact-nonnegative-integer?])) ; direct preference to a kernel primitive