Merge branch 'working'

* working:
  update untyped_eval to 1.5

diff --combined topics/week7_untyped_evaluator.mdwn
index 683a0fd,6e5480a..f18bdc6
--- 1/topics/week7_untyped_evaluator.mdwn
--- 2/topics/week7_untyped_evaluator.mdwn
+++ b/topics/week7_untyped_evaluator.mdwn
@@@ -310,7 -310,7 +310,7 @@@ In later weeks, we will see more exampl
  Getting, reading, and compiling the source code
  -----------------------------------------------
  
- You can download the source code for the intepreter [[here|/code/untyped_full-1.4.tgz]]. That link will always give you the latest version. We will update it as we find any issues. Let us know about any difficulties you experience.
+ You can download the source code for the intepreter [[here|/code/untyped_full-1.5.tgz]]. That link will always give you the latest version. We will update it as we find any issues. Let us know about any difficulties you experience.
  
  When you unpack the downloaded source code, you will get a folder with the following contents, sorted here by logical order rather than alphabetically.
  
@@@ -475,7 -475,7 +475,7 @@@ Here is some more sample inputs, each o
      /* note that it's not f x (g y) (h z) */
      "strings" /* you can input these and pass them around, but can't perform any operations on them */
  
 -Predefined combinators include: `S`, `K` (same as `const`), `I` (same as `id`), `B` (same as `(o)`, occurring in prefix not infix position), `C` (same as `flip`), `T`, `V` (the Church pairing combinator), `W`, `M` (better known as `ω`), and `L`.
 +Predefined combinators include: `S`, `K` (same as `const`), `I` (same as `id`), `B` (same as `(o)`, occurring in prefix not infix position), `C` (same as `flip`), `T` (same as `flip ($)`), `V` (the Church pairing combinator), `W`, `M` (better known as `ω`), and `L`.
  
  The parser also accepts `letrec ... in ...` terms, but currently there is no implementation for how to reduce/interpret these (that's for a later assignment), so you'll just get an error.