resume in loca / versioned struct

pitfall/fontkit/clone.rkt

@@ -1,6 +1,7 @@
 #lang fontkit/racket
+(require racket/serialize)
 (provide cloneDeep)
 
 (define (cloneDeep val)
-  (parameterize ([print-graph #t])
-    (read (open-input-string (~s val)))))
+  (deserialize (serialize val)))
+

pitfall/fontkit/font.rkt

@@ -80,7 +80,7 @@ https://github.com/mbutterick/fontkit/blob/master/src/TTFFont.js
 ;; The size of the font’s internal coordinate grid
 (define/contract (unitsPerEm this)
   (->m number?)
-  (FT_FaceRec-units_per_EM (· this ft-face)))
+  (hash-ref (send this _getTable 'head) 'unitsPerEm))
 
 
 ;; The font’s [ascender](https://en.wikipedia.org/wiki/Ascender_(typography))

pitfall/fontkit/loca.rkt

@@ -0,0 +1,21 @@
+#lang fontkit/racket
+(require restructure)
+(provide (all-defined-out))
+
+#|
+approximates
+https://github.com/mbutterick/fontkit/blob/master/src/tables/loca.js
+|#
+
+(define-subclass RVersionedStruct (Rloca))
+
+(define loca (make-object Rloca
+               (λ (this) (hash-ref (send this _getTable 'head) 'indexToLocFormat)) 
+               (dictify
+
+                
+                )))
+
+(test-module
+ )
+

pitfall/fontkit/subset.rkt

@@ -70,10 +70,10 @@ https://github.com/mbutterick/fontkit/blob/master/src/subset/TTFSubset.js
        (send this _addGlyph gid))
 
   (define maxp (cloneDeep (send (· this font) _getTable 'maxp)))
-  ;; (hash-set! maxp 'numGlyphs (length (· this glyf))) ; todo
+  (hash-set! maxp 'numGlyphs (length (· this glyf))) ; todo
 
   ;; todo
-  ;;     this.loca.offsets.push(this.offset);
+  (hash-update! (send (· this font) _getTable 'loca) 'offsets (λ (val) (push-end! val (· this offset))))
   ;; Tables.loca.preEncode.call(this.loca);
 
   (define head (cloneDeep (send (· this font) _getTable 'head)))

pitfall/fontkit/tables.rkt

@@ -8,4 +8,4 @@
                     (r+p . TABLE-ID-STRINGS)
                     (define ID (make-hasheq (map cons (list 'TABLE-ID ...) (list TABLE-ID ...)))))))
 
-(define-table-decoders table-decoders maxp hhea head)
+(define-table-decoders table-decoders maxp hhea head loca)

pitfall/restructure/main.rkt

@@ -2,6 +2,7 @@
 
 (r+p "number.rkt"
      "struct.rkt"
+     "versioned-struct.rkt"
      "string.rkt"
      "array.rkt"
      "bitfield.rkt"

pitfall/restructure/struct.rkt

@@ -13,7 +13,7 @@ https://github.com/mbutterick/restructure/blob/master/src/Struct.coffee
   (for ([(k v) (in-dict assocs)])
        (hash-set! fields k v))
 
-  (define/overment (decode stream [parent #f] [length 0])
+  (define/override (decode stream [parent #f] [length 0])
     (define res (_setup stream parent length))
     (_parseFields stream res fields)
     #;(hash-set! (hash-ref res '_props) '_currentOffset (· stream pos))

pitfall/restructure/versioned-struct.rkt

@@ -0,0 +1,21 @@
+#lang restructure/racket
+(require racket/dict "struct.rkt")
+(provide (all-defined-out))
+
+#|
+approximates
+https://github.com/mbutterick/restructure/blob/master/src/VersionedStruct.coffee
+|#
+
+(define-subclass RStruct (RVersionedStruct type [versions (dictify)])
+  
+  (define/override (decode stream [parent #f] [length 0])
+    (define res (send this _setup stream parent length))
+    (define version (cond
+                      [(procedure? type) (type parent)]
+                      [(is-a? type RBase) (send type decode stream)]
+                      [else (raise-argument-error 'decode "way of finding version" type)]))
+    (report version 'yay)
+    #;(_parseFields stream res fields)
+    #;(send this process res stream)
+    res))