[opportunistically avoid a matchesLhss call
Helmut Grohne <grohne@cs.uni-bonn.de>**20140725132317
 Ignore-this: cdc62af5ed4bdd611df33d0601c11962
] hunk ./src/Igor2/Data/Hypotheses.hs 246
-          b2 <- matchLhss p2 p1
hunk ./src/Igor2/Data/Hypotheses.hs 247
-            else if b2 then return (p2:ps)
-                 else liftM (p1:) (leastPatterns ps p2)
-        
+            else do b2 <- matchLhss p2 p1
+                    if b2 then return (p2:ps)
+                      else liftM (p1:) (leastPatterns ps p2)
+