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-rw-r--r--js/life.combinators.js30
1 files changed, 16 insertions, 14 deletions
diff --git a/js/life.combinators.js b/js/life.combinators.js
index 452c767..eeae17b 100644
--- a/js/life.combinators.js
+++ b/js/life.combinators.js
@@ -1,16 +1,16 @@
 /*
-identity		I	a → a
-constant		K	a → b → a
-apply			A	(a → b) → a → b
-thrush			T	a → (a → b) → b
-duplication	    W	(a → a → b) → a → b
-flip			C	(a → b → c) → b → a → c
-compose			B	(b → c) → (a → b) → a → c
-substitution    S	(a → b → c) → (a → b) → a → c
-chain			S_³ (a → b → c) → (b → a) → b → c
-converge		S2³ (b → c → d) → (a → b) → (a → c) → a → d
-psi				P	(b → b → c) → (a → b) → a → a → c
-fix-point4	    Y	(a → a) → a
+identity        I   a → a
+constant        K   a → b → a
+apply           A   (a → b) → a → b
+thrush          T   a → (a → b) → b
+duplication     W   (a → a → b) → a → b
+flip            C   (a → b → c) → b → a → c
+compose         B   (b → c) → (a → b) → a → c
+substitution    S   (a → b → c) → (a → b) → a → c
+chain           S_³ (a → b → c) → (b → a) → b → c
+converge        S2³ (b → c → d) → (a → b) → (a → c) → a → d
+psi             P   (b → b → c) → (a → b) → a → a → c
+fix-point4      Y   (a → a) → a
 
 ref:
 https://www.willtaylor.blog/combinators-and-church-encoding-in-javscript/
@@ -22,7 +22,7 @@ const A  = f => x => f (x)
 const T  = x => f => f (x)
 const W  = f => x => f (x) (x)
 const C  = f => y => x => f (x) (y)
-const B  = f => g => x => f (g (x)) // FIXME: but what happens when, say, g is a value like TRUE and not a function?
+const B  = f => g => x => f (g (x))
 const S  = f => g => x => f (x) (g (x))
 const S_ = f => g => x => f (g (x)) (x)
 const S2 = f => g => h => x => f (g (x)) (h (x))
@@ -42,13 +42,14 @@ const Y  = f => (g => g (g)) (g => f (x => g (g) (x)))
 // S2(I)(I)(I)(1) // 1
 // P(I)(I)(1)(2) // 1
 // Y(I)(1) // 1
+
 (function() {
     console.log('validating combinators');
     console.assert(I(1) === 1, 'I failed');
     console.assert(K(1)(2) === 1, 'K failed');
     console.assert(A(I)(1) === 1, 'A failed');
     console.assert(T(1)(I) === 1, 'T failed');
-    console.assert(W(I)(1) === 1, 'W failed');
+    console.assert(W(I)(1) === 1, 'W failed'); // FIXME: Does this really work?
     console.assert(C(I)(1)(2) === 1, 'C failed');
     console.assert(B(I)(I)(1) === 1, 'B failed');
     console.assert(S(I)(I)(1) === 1, 'S failed');
@@ -69,6 +70,7 @@ const nextBoardState = B (A (B (A (K (A (I)))))) (A (B (A (K (A (I))))))
 // validate countLiveNeighbors rules
 (function() {
     // FIXME: I think I messed up these test values, maybe?
+    // FIXME: I also don't think this'll work given that the combinators will only grok 1 arg that is another combinator...right?
     console.log('validating countLiveNeighbors');
     console.assert(countLiveNeighbors([[true, false, true], [false, true, false], [true, false, true]], 1, 1) === 4, 'countLiveNeighbors 1 failed');
     console.assert(countLiveNeighbors([[true, false, true], [false, true, false], [true, false, true]], 0, 0) === 2, 'countLiveNeighbors 2 failed');