spade-0.1.0.9: samples/concurrency.spd

proc thread1(r)
  for i = 1 to 500
    let rv = readref(r)
    writeref(r, (rv + 1))
  endfor
endproc
let ref = newref(0)
let t = startthread(thread1)
await(t)
print(readref(ref))