X-Git-Url: http://lambda.jimpryor.net/git/gitweb.cgi?p=lambda.git;a=blobdiff_plain;f=index.mdwn;h=8f0e0c6ea756a95be6b19a1b6cdc3f13c6c1029d;hp=7adc9d5f8476f200464b8488bf9d8746277a719e;hb=cd8b8c25ea0a23ef2ef148a8504913aef8428ac1;hpb=c34fbdb0806c93ae519eddec85bc7777e463b9b3

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@@ -110,11 +110,22 @@ The [[differences between our made-up language and Scheme, OCaml, and Haskell|ro
 [[More on Lists|topics/week3 lists]] (expanded on Sunday);
 [[What is computation?|topics/week3_what_is_computation]];
 Reduction Strategies and Normal Forms (in progress);
-Usefulness of `()` (in progress);
-[[Combinatory Logic|topics/week3 combinatory logic]];
+[[Unit and its usefulness|topics/week3 unit]] (posted on Wednesday);
+[[Combinatory Logic|topics/week3 combinatory logic]] (revised on Monday and Tuesday);
 [[Homework|exercises/assignment3]]
 
-> Also, by this point you should be able to handle all of *The Little Schemer* except for Chapters 9 and 10. Chapter 9 covers what is going on under the hood with `letrec`, and that will be our topic for next week.
+> Also, by this point you should be able to handle all of *The Little Schemer* except for Chapters 9 and 10. Chapter 9 covers what is going on under the hood with `letrec`, and that will be our topic for next week. You can also read Chapter 4 of Hankin on Combinatory Logic.
+
+> We posted [[answers to Week 2's homework|exercises/assignment2_answers]].
+
+(**Week 4**) Thursday 19 February 2015
+
+> Topics: [[!img images/tabletop_roleplaying.png size="240x240" alt="Hey, no recursing"]]
+[[Yes, recursing|topics/week4_fixed_point_combinators]];
+[[More about fixed point combinators|topics/week4_more_about_fixed_point_combinators]];
+Towards types (in progress)
+
+> Now you can read Sections 3.1 and 6.1 of Hankin; and browse the rest of Hankin Chapter 6, which should look somewhat familiar.
 
 
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