[speed up instance Term Type method equal
Helmut Grohne <grohne@cs.uni-bonn.de>**20150204085407
 Ignore-this: 2da25f070b42b75d00556114790ee226
 
 Every time it would hit an AppT, it would first unfold the whole AppT tree to
 determine that indeed an application sits at the root. By spelling out this
 case avoiding unfoldAppT, we can speed up igor2 on the test suite by 1.8%.
] hunk ./src/Syntax/Type.hs 219
+    -- The extra case for AppT is also covered in the general case, but
+    -- spelling it out here speeds things up considerably by avoiding the
+    -- unfoldAppT.
+    equal (AppT l1 l2) (AppT r1 r2) = equal l1 r1 && equal l2 r2