ion, compute a type for its body in an extended context; to compute a type for an application, compute types for its left and right components, and check that they match appropriately. Lets use the algorithm to compute a type for a = [x: ][x: ]x. FAILURE: no rule applies because x 2 Dom (x: ) x: ; x: valid x: ; x: ` x : ? x: ` [x: ]x : ! ? ` [x: ][x: ]x : ! !? (1) This system fails to derive th...