test

 

#light

namespace ViLogo

 module World =

    open System

    type World =
        {
            pos : (float * float)
            angle : float
            penDown : bool
        }
    with 
        static member init = {pos = (0.0, 0.0); angle = Math.PI/2.0; penDown = true}

    type Command = 
        |Forward of float
        |Turn of float
        |Zero
        |Angle of float
        |Pos of (float * float)
        |Erase
        |PenDown of bool

    type CommandResult = int

    let executeCommand command world = 
        match command with
        |Forward d ->   let x = fst world.pos + d * Math.Cos(world.angle)
                        let y = snd world.pos + d * Math.Sin(world.angle)
                        None, {world with pos = (x,y)}
        |Turn a ->  None, {world with angle = world.angle + a*Math.PI/180.0}
        |Zero -> None, World.init
        |Angle a ->  None, {world with angle = a*Math.PI/180.0}
        |Pos (x, y) -> None, {world with pos = (x,y)}
        |Erase -> None, world
        |PenDown b -> None, {world with penDown = b}