From: Jim Pryor
Date: Sat, 16 Oct 2010 18:13:35 +0000 (-0400)
Subject: alternate Y1,Y2 tweak
X-Git-Url: http://lambda.jimpryor.net/git/gitweb.cgi?p=lambda.git;a=commitdiff_plain;h=7c8829dbea0cfaa2fedfb7d6fdd46d1558e9e68a
alternate Y1,Y2 tweak
Signed-off-by: Jim Pryor
---
diff --git a/hints/assignment_4_hint_3_alternate_1.mdwn b/hints/assignment_4_hint_3_alternate_1.mdwn
index 12ddbd6b..c62d620d 100644
--- a/hints/assignment_4_hint_3_alternate_1.mdwn
+++ b/hints/assignment_4_hint_3_alternate_1.mdwn
@@ -9,15 +9,15 @@ Alternate strategy for Y1, Y2
in
C
-is implemented using regular, non-mutual recursion, like this (`f'` is a variable not occurring free in `A`, `B`, or `C`):
+is implemented using regular, non-mutual recursion, like this (`u` is a variable not occurring free in `A`, `B`, or `C`):
- let rec f' g x = (let f = f' g in A)
- in let rec g y = (let f = f' g in B)
- in let f = f' g in C
+ let rec u g x = (let f = u g in A)
+ in let rec g y = (let f = u g in B)
+ in let f = u g in C
or, expanded into the form we've been working with:
- let f' = Y (\f' g x. (\f. A) (f' g)) in
- let g = Y (\g y. (\f. B) (f' g)) in
- let f = f' g
+ let u = Y (\u g x. (\f. A) (u g)) in
+ let g = Y (\g y. (\f. B) (u g)) in
+ let f = u g