Fs.read_at.loop: def of mylsm-lsm-store@0.6.0.1
Import: import mylsm-lsm-store@0.6.0.1/src/Fs.bend as Fs
Lines 282-318 of mylsm-lsm-store@0.6.0.1/src/Fs.bend: https://jend.leeeet.dev/read.txt?path=mylsm-lsm-store@0.6.0.1/src/Fs.bend&start_line=282&end_line=318

import Base
import bend-kit-bytes@0.3.2.0/bytes.bend as StorageBytes

# Assembles a positional read from bounded chunks without moving the file cursor.
def read_at.loop(
  fuel: Nat,
  state: ReadAtState
) -> IO(
  File & Result<&1, &1, U32 & String, StorageBytes.Bytes>
):
  match fuel:
    case 0n: read_at.exhausted(state)
    case 1n+rest:
      match state:
        case ReadAtNeed{file, +offset, +remaining, chunks}:
          match remaining:
            case 0n: read_at.finish(file, chunks)
            case 1n+_:
              do IO<File & Result<&1, &1, U32 & String, StorageBytes.Bytes>>:
                pair : File & Result<&1, &1, U32 & String, List<&2, U32>> <-
                  File.read_at(file, U32.from_nat(offset),
                    U32.from_nat(Nat.min(8192n, remaining)))
                read_at.loop(rest,
                  ReadAtRead{pair, offset, remaining, chunks})
        case ReadAtRead{pair, offset, +remaining, chunks}:
          match pair:
            case (file, Fail{error}):
              IO.pure(File & Result<&1, &1, U32 & String, StorageBytes.Bytes>,
                (file, Fail{error}))
            case (file, Done{Nil{}}): read_at.finish(file, chunks)
            case (file, Done{values}):
              read_at.loop(rest, ReadAtPacked{file, offset, remaining,
                chunks, read_at.pack(8192, values)})
        case ReadAtPacked{file, offset, +remaining, chunks, buffer}:
          match buffer:
            case StorageBytes.Bytes{+len, buf}:
              read_at.loop(rest, ReadAtNeed{file,
                Nat.add(offset, U32.to_nat(len)),
                Nat.sub(remaining, U32.to_nat(len)),
                Con{StorageBytes.Bytes{len, buf}, chunks}})

Uses (22):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=File
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=File.read_at
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=IO
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=IO.bind
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=IO.pure
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.add
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.min
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.sub
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Pair
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Result
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Sigma
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=String
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.from_nat
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.to_nat
  https://jend.leeeet.dev/definition.txt?path=bend-kit-bytes@0.3.3.0/bytes.bend&name=Bytes
  https://jend.leeeet.dev/definition.txt?path=mylsm-lsm-store@0.6.0.1/src/Fs.bend&name=ReadAtState
  https://jend.leeeet.dev/definition.txt?path=mylsm-lsm-store@0.6.0.1/src/Fs.bend&name=read_at.exhausted
  https://jend.leeeet.dev/definition.txt?path=mylsm-lsm-store@0.6.0.1/src/Fs.bend&name=read_at.finish
  https://jend.leeeet.dev/definition.txt?path=mylsm-lsm-store@0.6.0.1/src/Fs.bend&name=read_at.pack