added more combinators to parser

Signed-off-by: Jim Pryor <profjim@jimpryor.net>

diff --git a/code/lambda.js b/code/lambda.js
index 50880fc..0eea4c9 100644 (file)
--- a/code/lambda.js
+++ b/code/lambda.js
@@ -450,42 +450,11 @@ try {
     }
 } catch (e) {}
 
-/*
-let true = K in
-let false = \x y. y in
-let and = \l r. l r false in
-let or = \l r. l true r in
-let pair = \u v f. f u v in
-let triple = \u v w f. f u v w in
-let succ = \n s z. s (n s z) in
-let pred = \n s z. n (\u v. v (u s)) (K z) I in
-let ifzero = \n. n (\u v. v (u succ)) (K 0) (\n withp whenz. withp n) in
-let add = \m n. n succ m in
-let mul = \m n. n (\z. add m z) 0 in
-let mul = \m n s. m (n s) in
-let sub = (\mzero msucc mtail. \m n. n mtail (m msucc mzero) true) (pair 0 I) (\d. d (\a b. pair (succ a) (K d))) (\d. d false d) in
-let min = \m n. sub m (sub m n) in
-let max = \m n. add n (sub m n) in
-let lt = (\mzero msucc mtail. \n m. n mtail (m msucc mzero) true (\x. true) false) (pair 0 I) (\d. d (\a b. pair (succ a) (K d))) (\d. d false d) in
-let leq = (\mzero msucc mtail. \m n. n mtail (m msucc mzero) true (\x. false) true) (pair 0 I) (\d. d (\a b. pair (succ a) (K d))) (\d. d false d) in
-let eq = (\mzero msucc mtail. \m n. n mtail (m msucc mzero) true (\x. false) true) (pair 0 (K (pair 1 I))) (\d. d (\a b. pair (succ a) (K d))) (\d. d false d) in
-let divmod = (\mzero msucc mtail. \n divisor.
-               (\dhead. n (mtail dhead) (\sel. dhead (sel 0 0)))
-              (divisor msucc mzero (\a b c. c x))
-              (\d m a b c. pair d m) )
-          (triple succ (K 0) I)
-          (\d. triple I succ (K d))
-          (\dhead d. d (\dz mz df mf drest sel. drest dhead (sel (df dz) (mf mz)))) in
-let div = \n d. divmod n d true in
-let mod = \n d. divmod n d false in
-let Y = \f. (\y. f(y y)) (\y. f(y y)) in
-let Z = (\u f. f(u u f)) (\u f. f(u u f)) in
-let fact = \y. y (\f n. ifzero n (\p. mul n (f p)) 1) in
-fact Z 3
-*/
 
 
 
+// Chris's original
+
 // // Basic data structure, essentially a LISP/Scheme-like cons
 // // pre-terminal nodes are expected to be of the form new cons(null, "string")
 // function cons(car, cdr) {

diff --git a/code/parse.js b/code/parse.js
index e3940b4..08ac5f0 100644 (file)
--- a/code/parse.js
+++ b/code/parse.js
@@ -208,8 +208,16 @@ var make_parse = function () {
                constant("I", make_lam(x, xx));
                constant("B", make_lam3(u, v, x, make_app(uu, make_app(vv, xx))));
                constant("C", make_lam3(u, v, x, make_app3(uu, xx, vv)));
-               constant("W", make_lam2(u, v, make_app3(uu, vv, vv)));
+
+               // trush \uv.vu = CI
                constant("T", make_lam2(u, v, make_app(vv, uu)));
+               // mockingbird \u.uu = SII
+               constant("M", make_lam(u, make_app(uu, uu)));
+               // warbler \uv.uvv = C(BM(BBT) = C(BS(C(BBI)I))I
+               constant("W", make_lam2(u, v, make_app3(uu, vv, vv)));
+               // lark \uv.u(vv) = CBM = BWB
+               constant("L", make_lam2(u, v, make_app(uu, make_app(vv, vv))));
+               // Y is SLL
 
        }
        make_constants();

diff --git a/lambda_evaluator.mdwn b/lambda_evaluator.mdwn
index 4a5b9dc..c9e2164 100644 (file)
--- a/lambda_evaluator.mdwn
+++ b/lambda_evaluator.mdwn
@@ -19,7 +19,7 @@ Blank lines are fine.
 
 *Abbreviations*: In an earlier version, you couldn't use abbreviations. `\x y. y x x` had to be written `(\x (\y ((y x) x)))`. We've upgraded the parser though, so now it should be able to understand any lambda term that you can.
 
-*Constants*: The combinators `S`, `K`, `I`, `C`, `B`, `W`, and `T` are pre-defined to their standard values. Also, integers will automatically be converted to Church numerals. (`0` is `\s z. z`, `1` is `\s z. s z`, and so on.)
+*Constants*: The combinators `S`, `K`, `I`, `C`, `B`, `W`, `T`, `M` (aka <code>&omega;</code>) and `L` are pre-defined to their standard values. Also, integers will automatically be converted to Church numerals. (`0` is `\s z. z`, `1` is `\s z. s z`, and so on.)