From b40a90f33c19449e68ced37946f3393820b8ef15 Mon Sep 17 00:00:00 2001
From: Matthew Butterick <mb@mbtype.com>
Date: Thu, 30 Mar 2017 20:07:09 -0700
Subject: [PATCH] structification

---
 pitfall/pitfall/minimal-pdf-source.rkt | 20 --------------
 pitfall/pitfall/parse.rkt              | 36 +++++++++-----------------
 pitfall/pitfall/render.rkt             | 16 +++++++++---
 pitfall/pitfall/struct.rkt             | 10 +++++--
 4 files changed, 32 insertions(+), 50 deletions(-)

diff --git a/pitfall/pitfall/minimal-pdf-source.rkt b/pitfall/pitfall/minimal-pdf-source.rkt
index 4efdffe8..cb4f301b 100644
--- a/pitfall/pitfall/minimal-pdf-source.rkt
+++ b/pitfall/pitfall/minimal-pdf-source.rkt
@@ -1,22 +1,2 @@
 #lang racket/base
 (require pitfall/struct pitfall/render)
-
-(define (io1)
-  (hasheq 'Pages "2 0 R" 'Type 'Catalog))
-
-(define (io2)
-  (hasheq 'Count 1 'Kids '("3 0 R") 'Type 'Pages 'MediaBox '(0 0 300 144)))
-
-(define (io3)
-  (hasheq 'Resources
-          (hasheq 'Font
-                  (hasheq 'F1 (hasheq 'Subtype 'Type1 'BaseFont 'Times-Roman
-                                      'Type 'Font)))
-          'Parent "2 0 R"
-          'Contents "4 0 R"
-          'Type 'Page))
-
-(define (io4)
-  ($stream (hasheq 'Length 55) #"  BT\n    /F1 18 Tf\n    0 0 Td\n    (Hello World) Tj\n  ET"))
-
-(display (cosexpr->string (list io1 io2 io3 io4)))
\ No newline at end of file
diff --git a/pitfall/pitfall/parse.rkt b/pitfall/pitfall/parse.rkt
index 38675d11..88751bd5 100644
--- a/pitfall/pitfall/parse.rkt
+++ b/pitfall/pitfall/parse.rkt
@@ -64,36 +64,24 @@
   #;(check-true (andmap byte? @pf-string{<1C2D3F>}))
   #;(check-true (andmap byte? @pf-string{<1C 2D 3F>})))
 
-(define (pf-array . xs) xs)
+(define (pf-array . xs) (co-array xs))
 
 (define (pf-dict . args)
-  (apply hasheq args))
+  (co-dict (apply hasheq args)))
 
 
 (define (pf-stream dict str)
   (define data (string->bytes/utf-8 str))
-  (when (not (equal? (hash-ref dict 'Length) (bytes-length data)))
+  (when (not (equal? (hash-ref (co-dict-dict dict) 'Length) (bytes-length data)))
     (raise-argument-error 'pf-stream
                           (format "~a bytes of data" (hash-ref dict 'Length))
                           (format "~a = ~v" (bytes-length data) data)))
-  ($stream dict data))
-
-(define-macro (pf-indirect-object OBJ-NUM GEN-NUM THING)
-  (with-syntax ([IO-ID (prefix-id "io" #'OBJ-NUM)])
-    #'(begin
-        (define (IO-ID #:name [name #f])
-          (if name
-              (string-join (map ~a '(OBJ-NUM GEN-NUM R)) " ")
-              THING))
-        (provide IO-ID)
-        IO-ID)))
-
-(define-macro (pf-indirect-object-ref (OBJ-NUM GEN-NUM "R"))
-  (with-syntax ([IO-ID (prefix-id "io" #'OBJ-NUM)])
-    #'(string-join '(OBJ-NUM GEN-NUM "R") " ")))
-
-(define-macro (pf-version NUM)
-  (with-pattern ([VERSION-ID (prefix-id "" #'version #:context #'NUM)])
-                #'(begin
-                    (define VERSION-ID NUM)
-                    (provide version))))
+  (co-stream dict data))
+
+(define (pf-indirect-object obj gen thing)
+  (co-io obj gen thing))
+
+(define-macro (pf-indirect-object-ref (OBJ GEN _))
+  #'(co-io-ref OBJ GEN))
+
+(define (pf-version num) (co-version num))
diff --git a/pitfall/pitfall/render.rkt b/pitfall/pitfall/render.rkt
index 5babff18..dc53002b 100644
--- a/pitfall/pitfall/render.rkt
+++ b/pitfall/pitfall/render.rkt
@@ -1,6 +1,14 @@
 #lang racket/base
-(require racket/string pitfall/struct)
-(provide (all-defined-out))
+(require (for-syntax racket/base)
+         racket/string pitfall/struct br/define)
+(provide (all-defined-out)
+         (all-from-out pitfall/struct)
+         (except-out (all-from-out racket/base) #%module-begin))
+
+(define-macro (mb . ARGS)
+  #'(#%module-begin
+     (cosexpr->string (list . ARGS))))
+(provide (rename-out [mb #%module-begin]))
 
 (define (cosexpr->string x)
   (define str
@@ -13,10 +21,10 @@
                     "\n<< "
                     (string-join
                      (for/list ([(k v) (in-hash x)])
-                               (string-join (list (loop k) (loop v)) " ")) " ")
+                       (string-join (list (loop k) (loop v)) " ")) " ")
                     " >> ")]
         [(symbol? x) (format "/~a" x)]
         [(number? x) (number->string x)]
-        [($stream? x) (string-append (loop ($stream-dict x)) (string-join (list "\nstream" (format "~a" ($stream-data x)) "endstream") "\n"))]
+        [(co-stream? x) (string-append (loop (co-stream-dict x)) (string-join (list "\nstream" (format "~a" (co-stream-data x)) "endstream") "\n"))]
         [else x])))
   (string-join (list "%%PDF1.1" str "%%EOF") "\n"))
\ No newline at end of file
diff --git a/pitfall/pitfall/struct.rkt b/pitfall/pitfall/struct.rkt
index 68052a17..ac14f7c4 100644
--- a/pitfall/pitfall/struct.rkt
+++ b/pitfall/pitfall/struct.rkt
@@ -1,3 +1,9 @@
 #lang racket/base
-(provide (struct-out $stream))
-(struct $stream (dict data) #:transparent)
\ No newline at end of file
+(provide (all-defined-out))
+
+(struct co-dict (dict) #:transparent)
+(struct co-array (items) #:transparent)
+(struct co-stream (dict data) #:transparent)
+(struct co-version (num) #:transparent)
+(struct co-io (obj gen thing) #:transparent)
+(struct co-io-ref (obj gen) #:transparent)
\ No newline at end of file