From 05c5b373163fa173e8884fbc38249b097ff8ab5c Mon Sep 17 00:00:00 2001
From: Matthew Butterick <mb@mbtype.com>
Date: Fri, 28 Feb 2014 12:09:25 -0800
Subject: [PATCH] macro of macros

---
 macro.rkt | 51 +++++++++++++++++++++++++++++++++++++--------------
 1 file changed, 37 insertions(+), 14 deletions(-)

diff --git a/macro.rkt b/macro.rkt
index 13abffb..28c5d06 100644
--- a/macro.rkt
+++ b/macro.rkt
@@ -1,21 +1,44 @@
 #lang racket/base
 (require (for-syntax racket/base))
 
-(provide macro-map)
+(provide macro-map macro-for-each)
 
-(define-syntax (macro-map stx)
-  (syntax-case stx ()
-    [(_ macro-name (list item0))
-     #'(cons
-        (macro-name item0) '())]
-    
-    [(_ macro-name (list item0 items ...))
-     #'(cons
-        (macro-name item0)
-        (macro-map macro-name (list items ...)))]))
 
+(define-syntax-rule (make-mappy-macro mappy-macro-name joining-proc ending-value)
+  (define-syntax mappy-macro-name
+    (syntax-id-rules ()
+      ;; convert quote form into list form
+      [(_ macro-name (quote (items (... ...))))
+       (mappy-macro-name macro-name (list items (... ...)))]
+      
+      ;; catch this case first, because it would also match the next one
+      [(_ macro-name (list item0))
+       (joining-proc 
+        (macro-name item0) ending-value)]
+      
+      [(_ macro-name (list item0 items (... ...)))
+       (joining-proc 
+        (macro-name item0) 
+        (mappy-macro-name macro-name (list items (... ...))))])))
 
-(define-syntax-rule (add x)
-  (+ 1 x))
+(make-mappy-macro macro-for-each begin (void))
+(make-mappy-macro macro-map cons '())
+
+
+
+(define-syntax-rule (add pair)
+  (+ (car pair) (cdr pair)))
+
+
+;; this matches first case - why?
+(macro-for-each add (list (cons 12 20)))
+
+
+;(macro-map add (list 24 25 30))
+;(macro-map add '(24 25 30))
+
+
+;(macro-map-old add (list 24 25 30))
+
+;(macro-for-each add '(24 25 30))
 
-(macro-map add (list 24 25 30))
\ No newline at end of file