## Announcements ##
+* [[Untyped lambda calculus evaluator|code/lambda_evaluator]] on this site
+
* This wiki will be undergoing lots of changes throughout the semester, and particularly in these first few days as we get it set up, migrate over some of the content from the previous time
we taught this course, and iron out various technical wrinkles. Please be patient. When you sit down to read the wiki, it's a good idea to always hit "Refresh" in your browser to make sure you're reading the latest additions and refinements of the website. (Sometimes these will be tweaks, other times very substantial. Updates will happen at miscellaneous hours, sometimes many times in a given day.)
- If you've eager to learn, though, you don't have to wait on us to be ready to serve you. You can go look at the [archived first version](http://lambda1.jimpryor.net) of this course. Just keep in mind that
+ If you're eager to learn, though, you don't have to wait on us to be ready to serve you. You can go look at the [archived first version](http://lambda1.jimpryor.net) of this course. Just keep in mind that
the text and links there haven't been updated. And/or you can get started on installing the software and ordering some of the books.
* As we mentioned in class, if you're following the course and would like to be emailed occasionally, send an email to <mailto:jim.pryor@nyu.edu>, saying "lambda" in the subject line. Most often, we will just post announcements to this website, rather than emailing you. But occasionally an email might be more appropriate.
> Topics:
[[Order in programming languages and natural language|topics/week1 order]];
-[[Introduction to functional programming|topics/week1]];
+[[Introduction to functional programming|topics/week1 kapulet intro]];
[[Homework|exercises/assignment1]];
-[[Advanced notes|topics/week1 advanced notes]]
+[[Advanced notes|topics/week1 kapulet advanced]]
(**Intermezzo**)
> Help on [[learning Scheme]], [[OCaml|learning OCaml]], and [[Haskell|learning Haskell]];
-The [[differences between our made-up language and Scheme, OCaml, and Haskell|rosetta1]] (in progress);
+The [[differences between our made-up language and Scheme, OCaml, and Haskell|rosetta1]];
[[What do words like "interpreter" and "compiler" mean?|ecosystem]] (in progress)
-(**[[Lambda Evaluator|code/lambda_evaluator]]**) Usable in your browser. It can help you check whether your answer to some of the homework questions works correctly.
+(**[[Lambda Evaluator|code/lambda evaluator]]**) Usable in your browser. It can help you check whether your answer to some of the (upcoming) homework questions works correctly.
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- There is also now a [library](/lambda_library) of lambda-calculus arithmetical and list operations, some relatively advanced.
+ There is also now a [library](/lambda library) of lambda-calculus arithmetical and list operations, some relatively advanced.
-->
(**Week 2**) Thursday 5 February 2015
-> Notes on their way...
+> Topics:
+[[Intro to the Lambda Calculus|topics/week2 lambda intro]];
+[[Advanced notes|topics/week2 lambda advanced]];
+[[Encoding Booleans, Tuples, Lists, and Numbers|topics/week2 encodings]];
+[[Homework|exercises/assignment2]]
+
+> Also, if you're reading the Hankin book, try reading Chapters 1-3. You will most likely need to come back again and read it multiple times; but this would be a good time to make the first attempt.
+
+> We posted [[answers to Week 1's homework|exercises/assignment1_answers]].
+
+(**Week 3**) Thursday 12 February 2015
+*We will continue to develop these notes over the next few days.*
+
+> Topics:
+[[Arithmetic with Church numbers|topics/week3_church_arithmetic]];
+[[More on Lists|topics/week3 lists]] (expanded on Sunday);
+[[What is computation?|topics/week3_what_is_computation]];
+[[Reduction Strategies and Normal Forms|topics/week3_evaluation_order]] (posted on Monday 23 Feb);
+[[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. 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);
+[[Homework|exercises/assignment4]]
+
+> 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.
+
+> If you're reading along in the Pierce book, we've now covered much of the material in his Chapters 1-7.
+
+> We posted [[answers to Week 3's homework|exercises/assignment3_answers]].
+
+(**Week 5**) Thursday 26 February 2015
+
+> *Note*: Jim will be updating and expanding the lecture notes by Tuesday, but doesn't want to delay any longer letting you have access to the drafts we (in part) presented from in seminar. But do come back and re-read the pages when the expanded versions are posted.
+
+> Topics:
+[[Simply-typed lambda calculus|topics/week5 simply typed]];
+[[System F|topics/week5 system F]];
+Types in OCaml and Haskell;
+Practical advice for working with OCaml and/or Haskell (all will be posted soon);
+[[Homework|exercises/assignment5]]
+
+> *There is some assigned reading for our next meeting.* This comes in two batches. The first batch consists of [[this footnote|readings/kaplan-plexy.pdf]] from Kaplan's *Demonstratives*. Also recommended, but not mandatory, is [[this selection|readings/king-on-schiffer.pdf]] from Chapter 4 of Jeff King's 2007 book *The Nature and Structure of Content*. The second batch consists of [[this paper|readings/rieppel-beingsthg.pdf]] from Michael Rieppel, a recent Berkeley Philosophy PhD, on Frege's "concept horse" problem. Also recommended, but not mandatory, is [[this selection|readings/king-on-logicism.pdf]] from Chapter 5 of King's book. (It reviews and elaborates his paper "[Designating propositions](http://philpapers.org/rec/KINDP)".)
+
+> If you're interested in the scholarly background on Frege's "concept horse" problem, here is [an entry point](http://philpapers.org/rec/PROWIF).
+
+> If you're reading along in Hankin, you can look at Chapter 7.
+
+> If you're reading along in the Pierce book, the chapters most relevant to this week's discussion are 22 and 23; though for context we also recommend at least Chapters 8, 9, 11, 20, and 29. We don't expect most of you to follow these recommendations now, or even to be comfortable enough yet with the material to be able to. We're providing the pointers as references that some might conceivably pursue now, and others later.
+
+(**Week 6**) Thursday March 5
+
+> We will be discussing the readings posted above.
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