Theorem: stringToElf_ignoresTrailing (One.lean)

State before:
s : List Char
⊢ stringToElf (s ++ [Char.ofNat 10]) = stringToElf s
Tactic:
simp only [stringToElf, ne_eq, decide_not, List.find?, List.not_mem_nil, beq_iff_eq, IsEmpty.forall_iff,
  forall_const, List.splitOn_last, List.filter_append, decide_True, Bool.not_true, not_false_iff,
  List.filter_cons_of_neg, List.filter_nil, List.append_nil]
State after:
no goals