From 6552d3f2cd0e81cea55b572cd3b72e4cbf7e4b72 Mon Sep 17 00:00:00 2001
From: Jon Rafkind <rafkind@racket-lang.org>
Date: Fri, 13 Jan 2012 13:10:29 -0700
Subject: [PATCH] [honu] allow classes to accept 0 constructor parameters. add
 'to' as a binary operator that creates a list of numbers

---
 collects/honu/core/main.rkt           |  1 +
 collects/honu/core/private/class.rkt  |  1 +
 collects/honu/core/private/honu2.rkt  | 48 ++++++++++++++++-----------
 collects/honu/core/private/parse2.rkt |  2 +-
 collects/tests/honu/for.honu          |  4 +--
 5 files changed, 33 insertions(+), 23 deletions(-)

diff --git a/collects/honu/core/main.rkt b/collects/honu/core/main.rkt
index ed16d51ba9..47a0090235 100644
--- a/collects/honu/core/main.rkt
+++ b/collects/honu/core/main.rkt
@@ -33,6 +33,7 @@
                                    [honu-var var]
                                    [honu-val val]
                                    [honu-for for]
+                                   [honu-to to]
                                    [honu-if if]
                                    [honu-quote quote]
                                    [honu-quasiquote quasiquote]
diff --git a/collects/honu/core/private/class.rkt b/collects/honu/core/private/class.rkt
index b5bec6f767..a0eb233921 100644
--- a/collects/honu/core/private/class.rkt
+++ b/collects/honu/core/private/class.rkt
@@ -26,6 +26,7 @@
 (define-honu-syntax honu-class
   (lambda (code context)
     (syntax-parse code #:literal-sets (cruft)
+      ;; FIXME: empty parenthesis for constructor arguments should be optional
       [(_ name (#%parens (~var constructor-argument (separate-ids (literal-syntax-class honu-comma) (literal-syntax-class honu-comma))))
           (#%braces method:honu-class-thing ...) . rest)
        (define class
diff --git a/collects/honu/core/private/honu2.rkt b/collects/honu/core/private/honu2.rkt
index 7103a032ba..967d317a7e 100644
--- a/collects/honu/core/private/honu2.rkt
+++ b/collects/honu/core/private/honu2.rkt
@@ -54,25 +54,7 @@
          #'rest
          #f)])))
 
-(provide honu-for)
-(define-honu-syntax honu-for
-  (lambda (code context)
-    (syntax-parse code #:literal-sets (cruft)
-                       #:literals (honu-equal honu-in)
-      [(_ iterator:id honu-equal start:honu-expression honu-to end:honu-expression
-          honu-do body:honu-expression . rest)
-       (values
-           #'(%racket (for/list ([iterator (in-range start.result
-                                                     end.result)])
-                        body.result))
-         #'rest
-         #t)]
-      [(_ iterator:id honu-in stuff:honu-expression
-          honu-do body:honu-expression . rest)
-       (values #'(%racket (for/list ([iterator stuff.result])
-                            body.result))
-               #'rest
-               #t)])))
+
 
 (provide honu-if)
 (define-honu-syntax honu-if
@@ -259,6 +241,10 @@
 (define-binary-operator honu-string=? 1 'left string=?)
 (define-binary-operator honu-modulo 2 'left modulo)
 
+(define-binary-operator honu-to 0.001 'left
+                        (lambda (left right)
+                          (for/list ([i (in-range left right)]) i)))
+
 (define-unary-operator honu-not 0.7 'left not)
 
 (define-binary-operator honu-equal 1 'left equal?)
@@ -372,7 +358,8 @@
     [pattern (~seq (~var first (id-except separator end))
                    (~seq (~var between (id-must-be separator))
                          (~var next (id-except separator end))) ...)
-             #:with (id ...) #'(first.x next.x ...)]))
+             #:with (id ...) #'(first.x next.x ...)]
+    [pattern (~seq) #:with (id ...) '()]))
 
 (begin-for-syntax
   (provide honu-declaration)
@@ -417,3 +404,24 @@
 (provide true false)
 (define true #t)
 (define false #f)
+
+(provide honu-for)
+(define-honu-syntax honu-for
+  (lambda (code context)
+    (syntax-parse code #:literal-sets (cruft)
+                       #:literals (honu-equal honu-in)
+                       #;
+      [(_ iterator:id honu-equal start:honu-expression honu-to end:honu-expression
+          honu-do body:honu-expression . rest)
+       (values
+           #'(%racket (for/list ([iterator (in-range start.result
+                                                     end.result)])
+                        body.result))
+         #'rest
+         #t)]
+      [(_ iterator:id honu-in stuff:honu-expression
+          honu-do body:honu-expression . rest)
+       (values #'(%racket (for/list ([iterator stuff.result])
+                            body.result))
+               #'rest
+               #t)])))
diff --git a/collects/honu/core/private/parse2.rkt b/collects/honu/core/private/parse2.rkt
index aba4c70930..a8fe645d0c 100644
--- a/collects/honu/core/private/parse2.rkt
+++ b/collects/honu/core/private/parse2.rkt
@@ -161,7 +161,7 @@
      (debug "Parse more: ~a unparsed ~a\n" parsed unparsed)
      (define output (if parsed
                       (honu->racket parsed)
-                      #'(begin)))
+                      #'(void)))
      (debug "Output ~a\n" output)
      (with-syntax ([output output]
                    [(unparsed-out ...) unparsed]
diff --git a/collects/tests/honu/for.honu b/collects/tests/honu/for.honu
index 9ae936ca86..0f8e18fd4c 100644
--- a/collects/tests/honu/for.honu
+++ b/collects/tests/honu/for.honu
@@ -1,9 +1,9 @@
 #lang honu
 
-for x = 1 + 5 to 10 do
+for x in 1 + 5 to 10 do
   printf("x is ~a\n" x)
 
-for x = 1 to 10 do {
+for x in 1 to 10 do {
     var y = x + 1;
     printf("x ~a y ~a\n", x, y)
 }