Function flattenCauseLoop

packages/effect/src/internal/cause.ts:480–509

(
  causes: Chunk.Chunk<Cause.Cause<unknown>>,
  flattened: Chunk.Chunk<HashSet.HashSet<unknown>>
)

/** @internal */
const flattenCauseLoop = (
  causes: Chunk.Chunk<Cause.Cause<unknown>>,
  flattened: Chunk.Chunk<HashSet.HashSet<unknown>>
): Chunk.Chunk<HashSet.HashSet<unknown>> => {
  // eslint-disable-next-line no-constant-condition
  while (1) {
    const [parallel, sequential] = pipe(
      causes,
      Arr.reduce(
        [HashSet.empty<unknown>(), Chunk.empty<Cause.Cause<unknown>>()] as const,
        ([parallel, sequential], cause) => {
          const [par, seq] = evaluateCause(cause)
          return [
            pipe(parallel, HashSet.union(par)),
            pipe(sequential, Chunk.appendAll(seq))
          ]
        }
      )
    )
    const updated = HashSet.size(parallel) > 0 ?
      pipe(flattened, Chunk.prepend(parallel)) :
      flattened
    if (Chunk.isEmpty(sequential)) {
      return Chunk.reverse(updated)
    }
    causes = sequential
    flattened = updated
  }
  throw new Error(getBugErrorMessage("Cause.flattenCauseLoop"))
}

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