1 files changed, 20 insertions, 0 deletions
diff --git a/algebraic-structures.private.stream.scm b/algebraic-structures.private.stream.scm
new file mode 100644
index 0000000..a268841
--- /dev/null
+++ b/algebraic-structures.private.stream.scm
@@ -0,0 +1,20 @@
+(module (algebraic-structures private stream) (<> unit fold reduce map1)
+  (import scheme
+          (srfi 41)
+          (streams utils)
+          (only (chicken base) assert))
+
+  (define (<> xs ys) (stream-append xs ys))
+
+  (define unit stream-null)
+
+  (define (fold f init xs)
+    (stream-fold (lambda (x acc) (f acc x))
+                 init
+                 xs))
+
+  (define (reduce f xs)
+    (stream-fold-one f xs))
+
+  (define (map1 f xs)
+    (stream-map f xs)))