change startOffset key name

xenomorph/xenomorph/array.rkt

@@ -28,7 +28,7 @@ https://github.com/mbutterick/restructure/blob/master/src/Array.coffee
     (define/augride (x:decode port parent)
       (define new-parent (if (x:int? @len)
                              (mhasheq 'parent parent
-                                      '_startOffset (pos port)
+                                      x:start-offset-key (pos port)
                                       '_currentOffset 0
                                       '_length @len)
                              parent))
@@ -40,7 +40,7 @@ https://github.com/mbutterick/restructure/blob/master/src/Array.coffee
                            [len (+ (pos port) len)]
                            ;; no resolved-len, but parent has length
                            [(and parent (not (zero? (dict-ref parent '_length))))
-                            (+ (dict-ref parent '_startOffset) (dict-ref parent '_length))]
+                            (+ (dict-ref parent x:start-offset-key) (dict-ref parent '_length))]
                            ;; no resolved-len or parent, so consume whole stream
                            [else +inf.0]))
          (for/list ([i (in-naturals)]

xenomorph/xenomorph/helper.rkt

@@ -6,7 +6,10 @@
          "generic.rkt")
 (provide (all-defined-out))
 
-(define x:version-key 'x:version) 
+(define x:version-key 'x:version)
+(define x:start-offset-key 'x:start-offset)
+
+(define private-keys (list 'parent x:start-offset-key '_currentOffset '_length))
 
 (define (dict-ref* d . keys)
   (for/fold ([d d])

xenomorph/xenomorph/lazy-array.rkt

@@ -18,7 +18,7 @@ https://github.com/mbutterick/restructure/blob/master/src/LazyArray.coffee
       (define len (resolve-length @len port parent))
       (define new-parent (if (x:int? @len)
                              (mhasheq 'parent parent
-                                      '_startOffset starting-pos
+                                      x:start-offset-key starting-pos
                                       '_currentOffset 0
                                       '_length @len)
                              parent))

xenomorph/xenomorph/pointer.rkt

@@ -39,10 +39,10 @@ https://github.com/mbutterick/restructure/blob/master/src/Pointer.coffee
         [(and @allow-null? (= offset @null-value)) #f] ; handle null pointers
         [else
          (define relative (+ (case @pointer-relative-to
-                               [(local) (dict-ref parent '_startOffset)]
+                               [(local) (dict-ref parent x:start-offset-key)]
                                [(immediate) (- (pos port) (send @offset-type x:size))]
-                               [(parent) (dict-ref (dict-ref parent 'parent) '_startOffset)]
-                               [(global) (or (dict-ref (find-top-parent parent) '_startOffset) 0)]
+                               [(parent) (dict-ref (dict-ref parent 'parent) x:start-offset-key)]
+                               [(global) (or (dict-ref (find-top-parent parent) x:start-offset-key) 0)]
                                [else (error 'unknown-pointer-style)])))
          (define ptr (+ offset relative))
          (cond

xenomorph/xenomorph/struct.rkt

@@ -17,7 +17,7 @@ https://github.com/mbutterick/restructure/blob/master/src/Struct.coffee
   (define mheq (make-hasheq))
   (dict-set*! mheq
               'parent parent
-              '_startOffset (pos port)
+              x:start-offset-key (pos port)
               '_currentOffset 0
               '_length len)
   mheq)
@@ -33,11 +33,9 @@ https://github.com/mbutterick/restructure/blob/master/src/Struct.coffee
                     (send type x:decode port sdr)))
     (unless (void? val)
       (dict-set! sdr key val))
-    (dict-set! sdr '_currentOffset (- (pos port) (dict-ref sdr '_startOffset)))
+    (dict-set! sdr '_currentOffset (- (pos port) (dict-ref sdr x:start-offset-key)))
     sdr))
 
-(define private-keys '(parent _startOffset _currentOffset _length))
-
 (define (dict->mutable-hash x)
   (define h (make-hasheq))
   (for ([(k v) (in-dict x)]

xenomorph/xenomorph/test/array-test.rkt

@@ -5,6 +5,7 @@
          "../number.rkt"
          "../pointer.rkt"
          "../generic.rkt"
+         "../helper.rkt"
          sugar/unstable/dict)
 
 #|
@@ -61,12 +62,12 @@ https://github.com/mbutterick/restructure/blob/master/test/Array.coffee
 (test-case 
  "array: decode to the end of parent if no length given"
  (parameterize ([current-input-port (open-input-bytes (bytes 1 2 3 4 5))])
-   (check-equal? (decode (x:array #:type uint8) (current-input-port) #:parent (mhash '_length 4 '_startOffset 0)) '(1 2 3 4))))
+   (check-equal? (decode (x:array #:type uint8) (current-input-port) #:parent (mhash '_length 4 x:start-offset-key 0)) '(1 2 3 4))))
 
 (test-case 
  "array: decode to the end of the stream if parent exists, but its length is 0"
  (parameterize ([current-input-port (open-input-bytes (bytes 1 2 3 4 5))])
-   (check-equal? (decode (x:array #:type uint8) (current-input-port) #:parent (mhash '_length 0 '_startOffset 0)) '(1 2 3 4 5))))
+   (check-equal? (decode (x:array #:type uint8) (current-input-port) #:parent (mhash '_length 0 x:start-offset-key 0)) '(1 2 3 4 5))))
 
 (test-case 
  "array: decode to the end of the stream if no parent and length is given"

xenomorph/xenomorph/test/pointer-test.rkt

@@ -18,12 +18,12 @@ https://github.com/mbutterick/restructure/blob/master/test/Pointer.coffee
 (test-case
  "pointer: decode should handle null pointers"
  (parameterize ([current-input-port (open-input-bytes (bytes 0))])
-   (check-false (decode (x:pointer) #:parent (mhash '_startOffset 50)))))
+   (check-false (decode (x:pointer) #:parent (mhash x:start-offset-key 50)))))
 
 (test-case
  "pointer: decode should use local offsets from start of parent by default"
  (parameterize ([current-input-port (open-input-bytes (bytes 1 53))])
-   (check-equal? (decode (x:pointer) #:parent (mhash '_startOffset 0)) 53)))
+   (check-equal? (decode (x:pointer) #:parent (mhash x:start-offset-key 0)) 53)))
 
 (test-case
  "pointer: decode should support immediate offsets"
@@ -34,19 +34,19 @@ https://github.com/mbutterick/restructure/blob/master/test/Pointer.coffee
  "pointer: decode should support offsets relative to the parent"
  (parameterize ([current-input-port (open-input-bytes (bytes 0 0 1 53))])
    (pos (current-input-port) 2)
-   (check-equal? (decode (x:pointer #:relative-to 'parent) #:parent (mhash 'parent (mhash '_startOffset 2))) 53)))
+   (check-equal? (decode (x:pointer #:relative-to 'parent) #:parent (mhash 'parent (mhash x:start-offset-key 2))) 53)))
 
 (test-case
  "pointer: decode should support global offsets"
  (parameterize ([current-input-port (open-input-bytes (bytes 1 2 4 0 0 0 53))])
    (pos (current-input-port) 2)
-   (check-equal? (decode (x:pointer #:relative-to 'global) #:parent (mhash 'parent (mhash 'parent (mhash '_startOffset 2))))
+   (check-equal? (decode (x:pointer #:relative-to 'global) #:parent (mhash 'parent (mhash 'parent (mhash x:start-offset-key 2))))
                  53)))
 
 (test-case
  "pointer: decode should support returning pointer if there is no decode type"
  (parameterize ([current-input-port (open-input-bytes (bytes 4))])
-   (check-equal? (decode (x:pointer uint8 'void) #:parent (mhash '_startOffset 0)) 4)))
+   (check-equal? (decode (x:pointer uint8 'void) #:parent (mhash x:start-offset-key 0)) 4)))
 
 (test-case
  "pointer: decode should support decoding pointers lazily"