why isn't ptr-offset set

fontland/fontland/subset.rkt

@@ -78,16 +78,23 @@ https://github.com/mbutterick/fontkit/blob/master/src/subset/CFFSubset.js
   (subset-add-glyph! ss 0)
   ss)
 
+(require racket/format racket/string)
+(define (bytes->hexes bs)
+  (string-join
+   (for/list ([b (in-bytes bs)])
+             (~r #:base 16 b #:min-width 2 #:pad-string "0"))  " "))
+
 (define (subsetCharstrings this)
   (set-cff-subset-charstrings! this null)
   (define gsubrs (make-hash))
   (for ([gid (in-list (subset-glyphs this))])
+       #R gid
+
        (set-cff-subset-charstrings!
         this
         (append (cff-subset-charstrings this)
                 (list (getCharString (cff-subset-cff this) gid))))
 
-       #R gid
        (define glyph (get-glyph (subset-font this) gid))
        ;; apparently path parsing is not necessary?
        #;(define path (hash-ref glyph 'path)) ;; this causes the glyph to be parsed
@@ -190,7 +197,6 @@ https://github.com/mbutterick/fontkit/blob/master/src/subset/CFFSubset.js
              'stringIndex (cff-subset-strings this)
              'globalSubrIndex (cff-subset-gsubrs this)))
 
-  #R top
   (encode CFFTop top stream)
 
   (error 'boom))

fontland/fontland/table/cff/cff-dict.rkt

@@ -30,7 +30,15 @@ https://github.com/mbutterick/fontkit/blob/master/src/cff/CFFDict.js
         [_  operands]))
 
     (define (encodeOperands type stream ctx operands)
-      (error 'cff-dict-encodeOperands-undefined))
+      (cond
+        [(list? type)
+         (for/list ([(op i) (in-indexed operands)])
+                   (car (encodeOperands (list-ref type i) stream ctx op)))]
+        [(xenomorphic? type) (encode type operands stream #:parent ctx)]
+        [(number? operands) (list operands)]
+        [(boolean? operands) (list (if operands 1 0))]
+        [(list? operands) operands]
+        [else (list operands)]))
 
     (define/override (post-decode val)
       (dict->mutable-hash val))
@@ -72,7 +80,8 @@ https://github.com/mbutterick/fontkit/blob/master/src/cff/CFFDict.js
 
       ret)
 
-    (define/augment (size dict parent [includePointers #true])
+    (augment [@size size])
+    (define (@size dict parent [includePointers #true])
       (define ctx
         (mhasheq x:parent-key parent
                  x:val-key dict
@@ -99,7 +108,8 @@ https://github.com/mbutterick/fontkit/blob/master/src/cff/CFFDict.js
 
       len)
 
-  (define/augment (encode stream dict parent)
-    (error 'cff-dict-encode-undefined))))
+    (augment [@encode encode])
+    (define (@encode stream dict parent)
+      (error 'cff-dict-encode-undefined))))
 
 (define (CFFDict [ops null]) (make-object CFFDict% ops))

fontland/fontland/table/cff/cff-operand.rkt

@@ -50,10 +50,12 @@ https://github.com/mbutterick/fontkit/blob/master/src/cff/CFFOperand.js
                    (let ([strs (cons (vector-ref FLOAT_LOOKUP n2) strs)])
                      (values strs #false))]))]))]))
 
-    (define/augment (size value-arg)
+    (define/augment (size value-arg _)
       ;; if the value needs to be forced to the largest size (32 bit)
       ;; e.g. for unknown pointers, set to 32768
-      (define value (if (hash-ref value-arg 'forceLarge #f) 32768 value-arg))
+      (define value (if (and (hash? value-arg) (hash-ref value-arg 'forceLarge #f))
+                        32768
+                        value-arg))
 
       (cond
         [(not (integer? value)) ; floating point

fontland/fontland/table/cff/cff-top.rkt

@@ -29,8 +29,11 @@ https://github.com/mbutterick/fontkit/blob/master/src/cff/CFFTop.js
     (define/augment (size value ctx)
       (error 'predefined-op-size-not-finished))
 
-    (define/augment (encode stream value ctx)
-      (error 'predefined-op-encode-not-finished))))
+    (augment [@encode encode])
+    (define (@encode stream value ctx)
+      #R (get-field pointer-relative-to @type)
+      (or (index-of @predefinedOps value)
+          (encode @type value stream #:parent ctx)))))
 
 (define (PredefinedOp predefinedOps type) (make-object PredefinedOp% predefinedOps type))
 
@@ -176,8 +179,8 @@ https://github.com/mbutterick/fontkit/blob/master/src/cff/CFFTop.js
   (x:versioned-struct
    #:pre-encode
    (λ (val)
-      ;; because fontkit depends on overloading 'version key, and we don't
-      (hash-set! val 'x:version (hash-ref val 'version))
+     ;; because fontkit depends on overloading 'version key, and we don't
+     (hash-set! val 'x:version (hash-ref val 'version))
      val)
    fixed16be
    (dictify