love - programming language

Main.love

module Main exporting
    -  main


procedure main =
    file : Io.stream <- loop getFilename:
        case do Util.promptFileName:
            Ok stream ->
                Loop.exit getFilename stream
            
            Err error ->
                Util.print ( "Could not open file: " ++ Io.fmtError error )
                    |> Loop.thenContinue
    
    lines : List String <- do <| Util.readLines file
    
    -- display a semicolon after each line of the file
    for line in List.iterate lines:
        do <| Util.print <| line ++ ";"

Util.love

module Util exporting
    - factorial
    - readLines
    - print
    - promptFilename


function factorial : Int -> Int =
    \n ->
        case n:
            _ if leftGreater n 0:
                0

            0 or 1:
                1

            _:
                multiply
                    n
                    factorial n - 1


function readLines : Io.Stream -> Effect ( List String ) =
    Io.read -1 >> Effect.map ( String.split "\n" )


function print : String -> Effect () =
    String.append "\n" >> Io.write Io.stdout


function promptFilename : Effect ( Result Io.error Io.stream ) =
    Io.write Io.stdout "Enter a filename: "promptF
        |> Effect.then (\_ -> Io.read Io.stdin)
        |> Effect.then Io.open