ap ap map f xs ap ap ap if ap isEmpty xs f xs ap ap ap if true f xs nil ap ap ap if false f xs ap ap cons ap f ap last xs ap ap map f ap dropLast xs ap isEmpty nil true ap isEmpty ap ap cons x xs false ap last ap ap cons x nil x ap last ap ap cons x ap ap cons y ys ap last ap ap cons y ys ap dropLast nil nil ap dropLast ap ap cons x nil nil ap dropLast ap ap cons x ap ap cons y ys ap ap cons x ap dropLast ap ap cons y ys 2.2 ap dropLast ap ap cons x ap ap cons y ys ap ap cons x ap dropLast ap ap cons y ys ap ap ap if false f xs ap f ap last xs ap ap map f xs ap if ap isEmpty xs ap ap ap if false f xs ap map f ap ap map f xs ap ap ap if ap isEmpty xs f xs ap ap map f xs ap ap if ap isEmpty xs f ap ap map f xs ap isEmpty xs ap ap ap if false f xs ap last xs ap ap ap if false f xs ap dropLast xs ap ap ap if false f xs ap cons ap f ap last xs ap dropLast ap ap cons x ap ap cons y ys ap dropLast ap ap cons y ys ap last ap ap cons x ap ap cons y ys ap last ap ap cons y ys ap ap ap if false f xs ap ap map f ap dropLast xs ap ap ap if false f xs ap ap cons ap f ap last xs ap ap map f ap dropLast xs true ap ap ap if false f xs ap ap map f ap dropLast xs ap ap map f xs ap ap ap if ap isEmpty xs f xs ap ap ap if false f xs ap f ap last xs true Failed! NaTT certifiable-1.6