X-Git-Url: http://lambda.jimpryor.net/git/gitweb.cgi?p=lambda.git;a=blobdiff_plain;f=monad_transformers.mdwn;h=b72c035cf5ec1a93e3e97a3b9a07dbdba0a6ff52;hp=efe35b2871d55dec0685839ad1d17bc86b71521b;hb=9fe62083953213cce34fc4458e36666902c5ee4b;hpb=0638e3b38097e20ebf645fe7cb1ecec4f17aef7a

diff --git a/monad_transformers.mdwn b/monad_transformers.mdwn
index efe35b28..b72c035c 100644
--- a/monad_transformers.mdwn
+++ b/monad_transformers.mdwn
@@ -10,7 +10,12 @@ So far, we've defined monads as single-layered things. Though in the Groenendijk
 	let bind (u: 'a reader) (f : 'a -> 'b reader) : 'b reader =
 		fun e -> (fun v -> f v e) (u e);;
 
-We've just beta-expanded the familiar `f (u e) e` into `(fun v -> f v e) (u e)`, in order to factor out the parts where any Reader monad is being supplied as an argument to another function. Then if we want instead to add a Reader layer to some arbitrary other monad M, with its own M.unit and M.bind, here's how we do it:
+We've just beta-expanded the familiar `f (u e) e` into `(fun v -> f v
+e) (u e)`, in order to factor out the parts where any Reader monad is
+being supplied as an argument to another function, as illustrated in
+the `bind` function in the following example. Then if we want instead
+to add a Reader layer to some arbitrary other monad M, with its own
+M.unit and M.bind, here's how we do it:
 
 	(* monadic operations for the ReaderT monadic transformer *)
 
@@ -29,7 +34,11 @@ We've just beta-expanded the familiar `f (u e) e` into `(fun v -> f v e) (u e)`,
 	let bind (u : ('a, M) readerT) (f : 'a -> ('b, M) readerT) : ('b, M) readerT =
 		fun e -> M.bind (u e) (fun v -> f v e);;
 
-Notice the key differences: where before we just returned `a`, now we instead return `M.unit a`. Where before we just supplied value `u e` of type `'a reader` as an argument to a function, now we instead `M.bind` the `'a reader` to that function. Notice also the differences in the types.
+Notice the key differences: where before we just returned `a`, now we
+instead return `M.unit a`. Where before we just supplied value `u e`
+of type `'a reader` as an argument to a function, now we instead
+`M.bind` the `'a reader` to that function. Notice also the differences
+in the types.
 
 What is the relation between Reader and ReaderT? Well, suppose you started with the Identity monad: