Using aubio from swift

Here is a short example showing how to read a sound file in swift:

import aubio
let path = Bundle.main.path(forResource: "example", ofType: "mp4")
if (path != nil) {
    let hop_size : uint_t = 512
    let a = new_fvec(hop_size)
    let b = new_aubio_source(path, 0, hop_size)
    var read: uint_t = 0
    var total_frames : uint_t = 0
    while (true) {
        aubio_source_do(b, a, &read)
        total_frames += read
        if (read < hop_size) { break }
    }
    print("read", total_frames, "frames at", aubio_source_get_samplerate(b), "Hz")
    del_aubio_source(b)
    del_fvec(a)
} else {
    print("could not find file")
}