X-Git-Url: http://lambda.jimpryor.net/git/gitweb.cgi?p=lambda.git;a=blobdiff_plain;f=manipulating_trees_with_monads.mdwn;h=d4b0bd877001f2d7a1e4c558e0ed16622fe55eaf;hp=1be499b023d19ea5b1da89c5ccb18002a3b5e1b9;hb=f5b1ef726e2cfa444df2b5fc50562822a90f0b03;hpb=a562d1d1ef9f380ddbe6e5f72aad3d4bfeaba716;ds=sidebyside

diff --git a/manipulating_trees_with_monads.mdwn b/manipulating_trees_with_monads.mdwn
index 1be499b0..d4b0bd87 100644
--- a/manipulating_trees_with_monads.mdwn
+++ b/manipulating_trees_with_monads.mdwn
@@ -1,10 +1,9 @@
 [[!toc]]
 
-
 Manipulating trees with monads
 ------------------------------
 
-This thread develops an idea based on a detailed suggestion of Ken
+This topic develops an idea based on a detailed suggestion of Ken
 Shan's.  We'll build a series of functions that operate on trees,
 doing various things, including replacing leaves, counting nodes, and
 converting a tree to a list of leaves.  The end result will be an
@@ -12,11 +11,11 @@ application for continuations.
 
 From an engineering standpoint, we'll build a tree transformer that
 deals in monads.  We can modify the behavior of the system by swapping
-one monad for another.  (We've already seen how adding a monad can add
+one monad for another.  We've already seen how adding a monad can add
 a layer of funtionality without disturbing the underlying system, for
 instance, in the way that the reader monad allowed us to add a layer
 of intensionality to an extensional grammar, but we have not yet seen
-the utility of replacing one monad with other.)
+the utility of replacing one monad with other.
 
 First, we'll be needing a lot of trees during the remainder of the
 course.  Here's a type constructor for binary trees: