X-Git-Url: http://lambda.jimpryor.net/git/gitweb.cgi?p=lambda.git;a=blobdiff_plain;f=hints%2Fassignment_7_hint_6.mdwn;h=e513284bd51d31b5eab302b3ab669e44957bf12f;hp=77b47926361117da69fd61bedd3054a44c613747;hb=0feebbaaa58403d836d7ea6166cf709dd3faf1a8;hpb=c022f10edea8eca8c68b010c07d4f72921e484c9

diff --git a/hints/assignment_7_hint_6.mdwn b/hints/assignment_7_hint_6.mdwn
index 77b47926..e513284b 100644
--- a/hints/assignment_7_hint_6.mdwn
+++ b/hints/assignment_7_hint_6.mdwn
@@ -20,13 +20,15 @@
 					(* if one_dpm isn't already false at (r, h),
 					   we want to check its behavior when updated with phi
 					   bind_set (unit_set one_dpm) phi === phi one_dpm; do you remember why? *)
-				    let (truth_value, _, _) = one_dpm (r, h)
+				    let (truth_value, r', h') = one_dpm (r, h)
 					in let truth_value' = truth_value && (truths (phi one_dpm) (r, h) = [])
 					(* new_dpm must return a (bool, r, h) *)
-                    in (truth_value', r, h)
+                    in (truth_value', r', h')
 				in unit_set new_dpm;;
 
 
+	**Thanks to Simon Charlow** for catching a subtle error in previous versions of this function. Fixed 1 Dec.
+
 *	Representing \[[and φ ψ]] is simple:
 
 		let and_op (phi : clause) (psi : clause) : clause =
@@ -36,6 +38,8 @@
 
 *	Here are `or` and `if`:
 
+	(These probably still manifest the bug Simon spotted.)
+
 		let or_op (phi : clause) (psi : clause) =
             fun one_dpm -> unit_set (
                 fun (r, h) ->