pipeline_stage   xtlang

(bind-func pipeline_stage:[FilterData*,!a,i64]*
  (lambda (filt depth)
    (let ((rate 1)
    (datasize (* rate (filt.push) depth))
    (d (alloc datasize))
    (b (QBuffer 0 0 datasize d))
    (p:i1 (or (refcheck filt prepush)
        (refcheck filt prepeek)
        (refcheck filt prepop)))
    (work (filt b))
    (lwork:[void]* work) ;; because rate is always 1 we ignore lwork
    (prework:[void]* (if p (work.prework) work)))
      (FilterData rate b b work lwork prework #f #t))))