T7294.hs:27:1: warning: [-Woverlapping-patterns (in -Wdefault)] Pattern match is redundant In an equation for ‘nth’: nth Nil _ = ... T7294.hs:27:5: warning: [-Winaccessible-code (in -Wdefault)] • Couldn't match type ‘'True’ with ‘'False’ Inaccessible code in a pattern with constructor: Nil :: forall a. Vec a 'Zero, in an equation for ‘nth’ • In the pattern: Nil In an equation for ‘nth’: nth Nil _ = undefined