Script to delete old podcasts

clean-podcasts.fsx

(***
Delete all files from subdirectories except most recently modified file  
Example: dotnet fsi clean-podcasts.fsx "C:\Downloads"
***)

open System.IO

// Get directories
let getDirectories topDir =
    let dir = DirectoryInfo(topDir)
    dir.GetDirectories()

// Operation to delete files
let deleteFiles (dir:DirectoryInfo) = 
    let files = 
        dir.GetFiles()
        |> Array.sortByDescending(fun file -> file.LastWriteTime)

    // Make sure that there are more than 1 episodes
    if files.Length > 1 then
        files
        |> Array.tail
        |> Array.iter(fun file -> file.Delete())


// run
let args = fsi.CommandLineArgs
let topDir = args.[1]

getDirectories topDir 
|> Array.iter(deleteFiles)