From 83b293e3e4d98ab680b719ad8cf3993aa0486abd Mon Sep 17 00:00:00 2001
From: Sergiu Ivanov <sivanov@colimite.fr>
Date: Sat, 5 Mar 2022 00:20:51 +0100
Subject: [PATCH] Type boolean-power/stream.

---
 scribblings/utils.scrbl | 11 ++++++++++-
 utils.rkt               | 22 ++++++++++------------
 2 files changed, 20 insertions(+), 13 deletions(-)

diff --git a/scribblings/utils.scrbl b/scribblings/utils.scrbl
index f6ff7a6..88f057c 100644
--- a/scribblings/utils.scrbl
+++ b/scribblings/utils.scrbl
@@ -477,4 +477,13 @@ Returns the @racket[n]-th Cartesian power of the Boolean domain.
 
 @examples[#:eval utils-evaluator
 (boolean-power 2)
-]}
\ No newline at end of file
+]}
+
+@defproc[(boolean-power/stream [n Integer])
+			       (Sequenceof (Listof Boolean))]{
+
+Like @racket[boolean-power], but returns a stream.
+
+@examples[#:eval utils-evaluator
+(stream->list (boolean-power/stream 2))
+]}
diff --git a/utils.rkt b/utils.rkt
index 50c0633..c71ad62 100644
--- a/utils.rkt
+++ b/utils.rkt
@@ -25,7 +25,7 @@
    update-vertices/unweighted update-graph dotit collect-by-key
    collect-by-key/sets ht-values/list->set hash->list/ordered
    multi-split-at lists-transpose in-random cartesian-product-2/stream
-   cartesian-product/stream boolean-power)
+   cartesian-product/stream boolean-power boolean-power/stream)
 
   (define-type Variable Symbol)
   (define-type (VariableMapping A) (Immutable-HashTable Variable A))
@@ -534,6 +534,13 @@
   (module+ test
     (test-case "boolean-power"
       (check-equal? (boolean-power 2) '((#f #f) (#f #t) (#t #f) (#t #t)))))
+
+  (: boolean-power/stream (-> Integer (Sequenceof (Listof Boolean))))
+  (define (boolean-power/stream n) (cartesian-product/stream (make-list n '(#f #t))))
+
+  (module+ test
+    (test-case "boolean-power/stream"
+      (check-equal? (stream->list (boolean-power/stream 2)) '((#f #f) (#f #t) (#t #f) (#t #t)))))
   )
 
 (require 'typed)
@@ -545,14 +552,13 @@
          update-vertices/unweighted update-graph dotit collect-by-key
          collect-by-key/sets ht-values/list->set hash->list/ordered
          multi-split-at lists-transpose in-random cartesian-product-2/stream
-         cartesian-product/stream boolean-power)
+         cartesian-product/stream boolean-power boolean-power/stream)
 
 ;;; Untyped section.
 
 (provide
  ;; Functions
- (contract-out [boolean-power/stream (-> number? (stream/c (listof boolean?)))]
-               [any->01 (-> any/c (or/c 0 1))]
+ (contract-out [any->01 (-> any/c (or/c 0 1))]
                [01->boolean (-> (or/c 0 1) boolean?)])
  ;; Contracts
  (contract-out [variable-mapping? contract?]
@@ -578,14 +584,6 @@
 ;;; Boolean operations
 ;;; ==================
 
-;;; Like boolean-power, but returns a stream whose elements the
-;;; elements of the Cartesian power.
-(define (boolean-power/stream n) (cartesian-product/stream (make-list n '(#f #t))))
-
-(module+ test
-  (test-case "boolean-power/stream"
-    (check-equal? (stream->list (boolean-power/stream 2)) '((#f #f) (#f #t) (#t #f) (#t #t)))))
-
 ;;; Converts any non-#f value to 1 and #f to 0.
 (define (any->01 x) (if x 1 0))