interface UnderlyingSource
optional
autoAllocateChunkSize: numberoptional
cancel: UnderlyingSourceCancelCallbackoptional
pull: UnderlyingSourcePullCallback<R>optional
start: UnderlyingSourceStartCallback<R>optional
type: ReadableStreamTypeautoAllocateChunkSize: numbercancel: UnderlyingSourceCancelCallbackpull: UnderlyingSourcePullCallback<R>start: UnderlyingSourceStartCallback<R>type: ReadableStreamType