From: Chris Barker
Date: Sat, 2 Oct 2010 19:15:18 +0000 (0400)
Subject: notes for week 4
XGitUrl: http://lambda.jimpryor.net/git/gitweb.cgi?p=lambda.git;a=commitdiff_plain;h=6495d054c734d27c17123d04d84f3b3cf798b743;hp=0bd2e02e48804480f7d899bc2c3ac486a578bfb7
notes for week 4

diff git a/assignment3.mdwn b/assignment3.mdwn
index 4e3c4f33..f93afd61 100644
 a/assignment3.mdwn
+++ b/assignment3.mdwn
@@ 4,7 +4,7 @@ Assignment 3
Once again, the lambda evaluator will make working through this
assignment much faster and more secure.
*Writing recursive functions on version 1 style lists*
+##Writing recursive functions on version 1 style lists##
Recall that version 1 style lists are constructed like this:
@@ 46,7 +46,7 @@ eq 3 3
Then `length mylist` evaluates to 3.
1. What does `head (tail (tail mylist))` evaluate to?
+1. Warmup: What does `head (tail (tail mylist))` evaluate to?
2. Using the `length` function as a model, and using the predecessor
function, write a function that computes factorials. (Recall that n!,
@@ 65,9 +65,17 @@ same length. That is,
listLenEq mylist (makeList meh (makeList meh nil))) ~~> false

4. Now write the same function, but don't use the length function (hint: use `leq` as a model).
+##Trees##
+
+Since we'll be working with linguistic objects, let's approximate
+trees as follows: a tree is a version 1 list
+a Church number is a tree, and
+if A and B are trees, then (makepair A B) is a tree.
+
+
+
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