+* [[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'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.
+
+<!--
+* As we mentioned in class, we're also going to schedule a session to discuss the weekly homeworks. If you'd like to participate in this, please complete [this Doodle poll](http://doodle.com/7xrf4w8xq4i9e5za). It asks when you are available on Tuesdays and Wednesdays.
+-->
+
+* The student session has been scheduled for Wednesdays from 5-6, in Linguistics room 104 (back of the first floor).
+
+ Those of you interested in additional Q&A but who can't make that time, let us know.
+
+ You should see these student sessions as opportunities to clear up lingering
+issues from material we've discussed, and help get a better footing for what
+we'll be doing the next week. It's expected you'll have made at least a serious start on that
+week's homework (due the following day) before the session.
+
+* Here is information about [[How to get the programming languages running on your computer|installing]]. If those instructions seem overwhelming, note that it should be possible to do a lot of this course using only demonstration versions of these languages [[that run in your web browser|browser]].
+
+* Henceforth, unless we say otherwise, every homework will be "due" by
+Wednesday morning after the Thursday seminar in which we refer to it.
+(Usually we'll post the assignment shortly before the seminar, but don't
+rely on this.) However, for every assignment there will be a "grace
+period" of one further week for you to continue working on it if you
+have trouble and aren't able to complete the assignment to your
+satisfaction by the due date. You shouldn't hesitate to talk to us---or
+each other!---about the assignments when you do have trouble. We don't
+mind so much if you come across answers to the assignment when browsing
+the web, or the Little Schemer book, or anywhere. So long as you can
+reason yourself through the solutions and experience for yourself the
+insights they embody.
+
+ We reserve the privilege to ruthlessly require you to
+explain your solutions in conversations at any point, in section or in
+class.
+
+ You should always *aim* to complete the assignments by the "due" date,
+as this will fit best with the progress of the seminar.
+
+ The assignments will tend to be quite challenging. Again, you should by
+all means talk amongst yourselves, and to us, about strategies and
+questions that come up when working through them.
+
+ We will not always be able to predict accurately which problems are
+easy and which are hard. If we misjudge, and choose a problem that is
+too hard for you to complete to your own satisfaction, it is still
+very much worthwhile (and very much appreciated) if you would explain
+what is difficult, what you tried, why what you tried didn't work, and
+what you think you need in order to solve the problem.
+
+
+
+
+(**Week 1**) Thursday 29 Jan 2015
+
+> Topics:
+[[Order in programming languages and natural language|topics/week1 order]];
+[[Introduction to functional programming|topics/week1 kapulet intro]];
+[[Homework|exercises/assignment1]];
+[[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]];
+[[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 (upcoming) homework questions works correctly.
+<!--
+ There is also now a [library](/lambda library) of lambda-calculus arithmetical and list operations, some relatively advanced.
+-->
+
+(**Week 2**) Thursday 5 February 2015
+> 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