 
 import Foundation
 
+let Usage = "usage: pdfcat file1 file2 ... output_file"
 let ProgressBarTotalTicks = 25
 
 enum Error: ErrorType {

    try main()
    print("")
} catch Error.NotEnoughArguments {
    printUsage(stderr)
} catch Error.InvalidPath(let path) {
    printError("\"\(path)\" is an invalid file path")
} catch Error.UnableToWrite(let path) {

    return booleanValue!
}

func main() throws {
    let args = Process.arguments
    if args.count == 0 {
        throw Error.NotEnoughArguments
    } else if ["usage", "help", "-h", "--help"].indexOf(args[0]) != nil {
        print(Usage)
        return
    } else if args.count < 3 {
        throw Error.NotEnoughArguments
