haskell: 13 new program suites + scoreboard 156/156 (775 tests)

collatz, palindrome, maybe, fizzbuzz, anagram, roman, binary, either,
primes, zipwith, matrix, wordcount, powers — all 18/18 programs green.
conformance.sh PROGRAMS array updated; scoreboard.md regenerated.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

lib/haskell/tests/program-zipwith.sx

@@ -0,0 +1,74 @@
+;; zipwith.hs — zip, zipWith, unzip operations.
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define
+  hk-as-list
+  (fn
+    (xs)
+    (cond
+      ((and (list? xs) (= (first xs) "[]")) (list))
+      ((and (list? xs) (= (first xs) ":"))
+        (cons (nth xs 1) (hk-as-list (nth xs 2))))
+      (:else xs))))
+
+(define
+  hk-zip-src
+  "addPair (x, y) = x + y\npairSum xs ys = map addPair (zip xs ys)\n\nscaleBy k xs = map (\\x -> x * k) xs\n\ndotProduct xs ys = sum (zipWith (*) xs ys)\n\nzipIndex xs = zip [0..length xs - 1] xs\n")
+
+(hk-test
+  "zip two lists"
+  (hk-as-list (hk-prog-val (str hk-zip-src "r = zip [1,2,3] [4,5,6]\n") "r"))
+  (list (list "Tuple" 1 4) (list "Tuple" 2 5) (list "Tuple" 3 6)))
+
+(hk-test
+  "zip unequal lengths — shorter wins"
+  (hk-as-list (hk-prog-val (str hk-zip-src "r = zip [1,2] [10,20,30]\n") "r"))
+  (list (list "Tuple" 1 10) (list "Tuple" 2 20)))
+
+(hk-test
+  "zipWith (+)"
+  (hk-as-list
+    (hk-prog-val (str hk-zip-src "r = zipWith (+) [1,2,3] [10,20,30]\n") "r"))
+  (list 11 22 33))
+
+(hk-test
+  "zipWith (*)"
+  (hk-as-list
+    (hk-prog-val (str hk-zip-src "r = zipWith (*) [2,3,4] [10,10,10]\n") "r"))
+  (list 20 30 40))
+
+(hk-test
+  "dotProduct [1,2,3] [4,5,6] = 32"
+  (hk-prog-val (str hk-zip-src "r = dotProduct [1,2,3] [4,5,6]\n") "r")
+  32)
+
+(hk-test
+  "dotProduct unit vectors = 0"
+  (hk-prog-val (str hk-zip-src "r = dotProduct [1,0] [0,1]\n") "r")
+  0)
+
+(hk-test
+  "pairSum adds element-wise"
+  (hk-as-list
+    (hk-prog-val (str hk-zip-src "r = pairSum [1,2,3] [4,5,6]\n") "r"))
+  (list 5 7 9))
+
+(hk-test
+  "unzip separates pairs"
+  (hk-prog-val (str hk-zip-src "r = unzip [(1,2),(3,4),(5,6)]\n") "r")
+  (list
+    "Tuple"
+    (list ":" 1 (list ":" 3 (list ":" 5 (list "[]"))))
+    (list ":" 2 (list ":" 4 (list ":" 6 (list "[]"))))))
+
+(hk-test
+  "zip empty = []"
+  (hk-as-list (hk-prog-val (str hk-zip-src "r = zip [] [1,2,3]\n") "r"))
+  (list))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}