Wonder-Technology/Wonder.js

open WonderBsMost.Most

let _isFromEventStream = %bs.raw(
  `
  function(stream){
    var source = stream.source;
    return !!source.event && !!source.source;
  }
  `
)

let concatArray = streamArr =>
  switch Js.Array.length(streamArr) {
  | 0 => WonderBsMost.Most.just(Obj.magic(1))
  | _ =>
    streamArr
    ->ArraySt.sliceFrom(1)
    ->ArraySt.reduceOneParam(streamArr[0], (. stream1, stream2) =>
      _isFromEventStream(stream1) === true ? stream2->concat(stream1) : stream2->concat(stream1)
    )
  }