X-Git-Url: http://lambda.jimpryor.net/git/gitweb.cgi?p=lambda.git;a=blobdiff_plain;f=hints%2Fassignment_7_hint_1.mdwn;h=0d67cd91a9ed4d95f9cbc519d5c662250a26fc0c;hp=f7d5d288fc4a0fe7f9dcb79519cad2b703a59da9;hb=fbf7eb4bd166b7bdf656f1c5f12528a39954dc51;hpb=4e38540a3d46c09c41f6c4591ab9b39b401ce050

diff --git a/hints/assignment_7_hint_1.mdwn b/hints/assignment_7_hint_1.mdwn
index f7d5d288..0d67cd91 100644
--- a/hints/assignment_7_hint_1.mdwn
+++ b/hints/assignment_7_hint_1.mdwn
@@ -3,11 +3,13 @@
 
 *	Where they represent pegs as natural numbers, that corresponds to our representing locations in a store by their indexes in the store.
 
-*	Where they say "reference system," which they use the leter `r` for, that corresponds to what we've been calling "assignments", and use the letter `g` for.
+*	Where they say "reference system," which they use the leter `r` for, that corresponds to what we've been calling "assignments", and have been using the letter `g` for.
 
 *	Where they say `r[x/n]`, that's our `g{x:=n}`.
 
 *	Their function `g`, which assigns objects from the domain to pegs, corresponds to our store function, which assigns entities to indexes.
 
+*	At several places they talk about some things being *real extensions* of other things. This confused me at first, because they don't ever define a notion of "real extension." (They do define what they mean by "an extension.") At one point in the paper, it emerges that what they mean is what I'd call a *proper extension*: an extension which isn't identical to the original.
+
 *	[More hints](/hints/assignment_7_hint_2).