-tcfail020.hs:11: No instance for: `A [taDM]'
- arising from an instance declaration at tcfail020.hs:11
- When checking superclass constraints of an instance declaration
+tcfail020.hs:11:
+ No instance for: `A [a]'
+ arising from an instance declaration, at tcfail020.hs:11
+ Available context: (A [a])
+ From the superclasses of the instance declaration
+
Compilation had errors