From e7823c4dacf4247379968129d4b992b27fa1c475 Mon Sep 17 00:00:00 2001
From: Max New <maxsnew@gmail.com>
Date: Sun, 3 Nov 2013 23:43:24 -0600
Subject: [PATCH] Add unnamed repeat support

---
 pkgs/redex-pkgs/redex-lib/redex/private/enum.rkt | 16 +++++++++-------
 .../redex-lib/redex/private/preprocess-pat.rkt   | 10 ++++++++--
 2 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/pkgs/redex-pkgs/redex-lib/redex/private/enum.rkt b/pkgs/redex-pkgs/redex-lib/redex/private/enum.rkt
index 06c0e101af..863518d737 100644
--- a/pkgs/redex-pkgs/redex-lib/redex/private/enum.rkt
+++ b/pkgs/redex-pkgs/redex-lib/redex/private/enum.rkt
@@ -108,7 +108,7 @@
       (except/e var/e s)]
      [`(variable-prefix ,s)
       ;; todo
-      (error 'unimplemented "var-prefix")]
+      (unimplemented "var-prefix")]
      [`variable-not-otherwise-mentioned
       unused/e]
      [`hole
@@ -277,7 +277,7 @@
                    ;; Only works if there are no variables inside the repeat
                    (add-named-rep name named-pats)]
                   [`(repeat ,pat ,name ,mismatch)
-                   (error 'unimplemented)]
+                   (unimplemented "mismatch repeats")]
                   [else (loop sub-pat named-pats)]))
              named-pats
              sub-pats)]
@@ -470,7 +470,7 @@
       (except/e var/e s)]
      [`(variable-prefix ,s)
       ;; todo
-      (error 'unimplemented "var-prefix")]
+      (unimplemented "var-prefix")]
      [`variable-not-otherwise-mentioned
       unused-var/e]
      [`hole
@@ -522,7 +522,7 @@
                  (many/e (loop pat)
                          n)))]
              [`(repeat ,pat ,name ,mismatch)
-              (error 'unimplemented "mismatch-repeat")]
+              (unimplemented "mismatch-repeat")]
              [else (loop sub-pat)]))
         sub-pats))]
      [(? (compose not pair?)) 
@@ -560,8 +560,6 @@
    (many/e char/e)))
 
 (define integer/e
-  #; ;; Simple "turn down the volume" list
-  (from-list/e '(0 1 -1))
   (sum/e nats
          (map/e (λ (n) (- (+ n 1)))
                 (λ (n) (- (- n) 1))
@@ -599,7 +597,11 @@
            [(decomposition? term)
             (error 'unsupported "in-hole")]
            [(list? term)
-            (map rec term)]
+            (append*
+             (for/list ([sub-term (in-list term)])
+               (cond [(repeat? sub-term)
+                      (map rec (repeat-terms sub-term))]
+                     [else (list (rec sub-term))])))]
            [else term]))
    (rec term)])
 
diff --git a/pkgs/redex-pkgs/redex-lib/redex/private/preprocess-pat.rkt b/pkgs/redex-pkgs/redex-lib/redex/private/preprocess-pat.rkt
index 768fe27377..3d2b789a8f 100644
--- a/pkgs/redex-pkgs/redex-lib/redex/private/preprocess-pat.rkt
+++ b/pkgs/redex-pkgs/redex-lib/redex/private/preprocess-pat.rkt
@@ -5,6 +5,7 @@
 
          "2set.rkt"
          "env.rkt"
+         "error.rkt"
          "match-a-pattern.rkt")
 
 (provide preprocess
@@ -24,7 +25,7 @@
                 pat)]
       [`(mismatch-name ,n ,subpat)
        ;; TODO
-       (error 'unimplemented)]
+       (unimplemented "mismatch-name")]
       [`(in-hole ,p1 ,p2)
        (match-define (ann-pat subenv1 _)
                      (walk p1))
@@ -41,8 +42,10 @@
        (define ann-sub-pats
          (for/list ([sub-pat (in-list sub-pats)])
            (match sub-pat
+             [`(repeat ,p #f #f)
+              (ann-pat empty-env sub-pat)]
              [`(repeat ,p ,n ,m)
-              (error 'unimplemented)]
+              (unimplemented "named repeat")]
              [_ (walk sub-pat)])))
        
        (define list-env
@@ -125,3 +128,6 @@
 
 (define (pure-ann-pat pat)
   (ann-pat empty-env pat))
+
+(define (unimplemented pat-name)
+  (redex-error 'unsupported "generate-term #:i-th currently doesn't support pattern type: ~a" pat-name))