Use arrays even though there's probably no perf difference

Changes

1 changed files (+4/-4)

• Printf.lean
  • @@ -16,11 +16,11 @@ def PrintfType : Fmt → Type 1
    | .FEnd => PLift String def printf (fmt : String) : PrintfType <| toFmt fmt.toList := - let rec printfAux (fmt : Fmt) (acc : List Char) : PrintfType fmt := + let rec printfAux (fmt : Fmt) (acc : Array Char) : PrintfType fmt := match fmt with | .FArg fmt => fun x ↦ printfAux fmt <| acc ++ (toString x).toList - | .FChar c fmt => printfAux fmt <| acc ++ [c] - | .FEnd => .up acc.asString - printfAux (toFmt fmt.toList) [] + | .FChar c fmt => printfAux fmt <| acc.push c + | .FEnd => .up acc.toList.asString + printfAux (toFmt fmt.toList) #[] #eval printf "Hello * * *" (-1) [42, 69] "Meow" |>.down