import Std -- Basic indexing theorem test1 : #[1, 2, 3][0] = 1 := by cbv /-- info: theorem test1 : #[1, 2, 3][0] = 1 := of_eq_true (Eq.trans (congrFun' (congrArg Eq (Eq.refl 1)) 1) (eq_self 1)) -/ #guard_msgs in #print test1 theorem test2 : #[1, 2, 3][2] = 3 := by cbv /-- info: theorem test2 : #[1, 2, 3][2] = 3 := of_eq_true (Eq.trans (congrFun' (congrArg Eq (Eq.refl 3)) 3) (eq_self 3)) -/ #guard_msgs in #print test2 -- Optional indexing (in bounds) theorem test3 : #[1, 2, 3][1]? = some 2 := by cbv /-- info: theorem test3 : #[1, 2, 3][1]? = some 2 := of_eq_true (Eq.trans (congrFun' (congrArg Eq (Eq.refl (some 2))) (some 2)) (eq_self (some 2))) -/ #guard_msgs in #print test3 -- Optional indexing (out of bounds) theorem test4 : #[1, 2, 3][5]? = none := by cbv /-- info: theorem test4 : #[1, 2, 3][5]? = none := of_eq_true (Eq.trans (congrFun' (congrArg Eq (Eq.refl none)) none) (eq_self none)) -/ #guard_msgs in #print test4 -- Nested arrays theorem test5 : #[#[1, 2], #[3, 4]][1][0] = 3 := by cbv /-- info: theorem test5 : #[#[1, 2], #[3, 4]][1][0] = 3 := of_eq_true (Eq.trans (congrFun' (congrArg Eq (Eq.trans (GetElem.getElem.congr_simp { toList := [{ toList := [1, 2] }, { toList := [3, 4] }] }[1] { toList := [3, 4] } (Eq.refl { toList := [3, 4] }) 0 0 (Eq.refl 0) (of_decide_eq_true (id (Eq.refl true)))) (Eq.refl 3))) 3) (eq_self 3)) -/ #guard_msgs in #print test5 -- Array of strings/other types theorem test6 : #["a", "b", "c"][0] = "a" := by cbv /-- info: theorem test6 : #["a", "b", "c"][0] = "a" := of_eq_true (Eq.trans (congrFun' (congrArg Eq (Eq.refl "a")) "a") (eq_self "a")) -/ #guard_msgs in #print test6