apl: ⊥ decode / ⊤ encode (mixed-radix; +11)

- apl-decode: Horner reduce; scalar base broadcasts to digit length
- apl-encode: right-to-left modulo + floor-div
- 24 60 60 ⊥ 2 3 4 → 7384, 24 60 60 ⊤ 7384 → 2 3 4
- pipeline 132/132

lib/apl/tests/pipeline.sx

@@ -544,3 +544,49 @@
     "∪/∩ identity: A ∪ A = ∪A"
     (mkrv (apl-run "1 2 1 ∪ 1 2 1"))
     (list 1 2)))
+
+(begin
+  (apl-test
+    "⊥ decode: 2 2 2 ⊥ 1 0 1 → 5"
+    (mkrv (apl-run "2 2 2 ⊥ 1 0 1"))
+    (list 5))
+  (apl-test
+    "⊥ decode: 10 10 10 ⊥ 1 2 3 → 123"
+    (mkrv (apl-run "10 10 10 ⊥ 1 2 3"))
+    (list 123))
+  (apl-test
+    "⊥ decode: 24 60 60 ⊥ 2 3 4 → 7384 (mixed-radix HMS)"
+    (mkrv (apl-run "24 60 60 ⊥ 2 3 4"))
+    (list 7384))
+  (apl-test
+    "⊥ decode: scalar base 2 ⊥ 1 0 1 0 → 10"
+    (mkrv (apl-run "2 ⊥ 1 0 1 0"))
+    (list 10))
+  (apl-test
+    "⊥ decode: 16 16 ⊥ 15 15 → 255"
+    (mkrv (apl-run "16 16 ⊥ 15 15"))
+    (list 255))
+  (apl-test
+    "⊤ encode: 2 2 2 ⊤ 5 → 1 0 1"
+    (mkrv (apl-run "2 2 2 ⊤ 5"))
+    (list 1 0 1))
+  (apl-test
+    "⊤ encode: 24 60 60 ⊤ 7384 → 2 3 4 (HMS)"
+    (mkrv (apl-run "24 60 60 ⊤ 7384"))
+    (list 2 3 4))
+  (apl-test
+    "⊤ encode: 2 2 2 2 ⊤ 13 → 1 1 0 1"
+    (mkrv (apl-run "2 2 2 2 ⊤ 13"))
+    (list 1 1 0 1))
+  (apl-test
+    "⊤ encode: 10 10 ⊤ 42 → 4 2"
+    (mkrv (apl-run "10 10 ⊤ 42"))
+    (list 4 2))
+  (apl-test
+    "⊤ encode: round-trip B⊥(B⊤N) = N"
+    (mkrv (apl-run "24 60 60 ⊥ 24 60 60 ⊤ 7384"))
+    (list 7384))
+  (apl-test
+    "⊥ decode: round-trip B⊤(B⊥V) = V"
+    (mkrv (apl-run "2 2 2 ⊤ 2 2 2 ⊥ 1 0 1"))
+    (list 1 0 1)))