haskell: Phase 10 conformance — statistics.hs (5/5) + newton.hs (5/5), Phase 10 complete

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

lib/haskell/tests/program-statistics.sx

@@ -0,0 +1,45 @@
+;; statistics.hs — mean, variance, std-dev on a [Double].
+;; Source: classic textbook example.
+;;
+;; Exercises Phase 10: `fromIntegral`, `/`, `sqrt`, list ops on `[Double]`.
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define
+  hk-stats-source
+  "mean xs = sum xs / fromIntegral (length xs)\n\nvariance xs = let m = mean xs\n                  sqDiff x = (x - m) * (x - m)\n              in sum (map sqDiff xs) / fromIntegral (length xs)\n\nstdDev xs = sqrt (variance xs)\n")
+
+(hk-test
+  "statistics.hs — mean [1,2,3,4,5] = 3"
+  (hk-prog-val (str hk-stats-source "r = mean [1.0,2.0,3.0,4.0,5.0]\n") "r")
+  3)
+
+(hk-test
+  "statistics.hs — mean [10,20,30] = 20"
+  (hk-prog-val (str hk-stats-source "r = mean [10.0,20.0,30.0]\n") "r")
+  20)
+
+(hk-test
+  "statistics.hs — variance [2,4,4,4,5,5,7,9] = 4"
+  (hk-prog-val
+    (str hk-stats-source "r = variance [2.0,4.0,4.0,4.0,5.0,5.0,7.0,9.0]\n")
+    "r")
+  4)
+
+(hk-test
+  "statistics.hs — stdDev [2,4,4,4,5,5,7,9] = 2"
+  (hk-prog-val
+    (str hk-stats-source "r = stdDev [2.0,4.0,4.0,4.0,5.0,5.0,7.0,9.0]\n")
+    "r")
+  2)
+
+(hk-test
+  "statistics.hs — variance of constant list = 0"
+  (hk-prog-val (str hk-stats-source "r = variance [5.0,5.0,5.0,5.0]\n") "r")
+  0)
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}