TLLRepl = proc (s: PLLStream; buf: pointer; bufLen: int): int

TLLStreamKind = enum
  llsNone, llsString, llsFile, llsStdIn

TLLStream = object of RootObj
  kind*: TLLStreamKind
  f*: File
  s*: string
  rd*, wr*: int
  lineOffset*: int
  repl*: TLLRepl

PLLStream = ref TLLStream

proc llStreamOpen(data: string): PLLStream {...}{.raises: [], tags: [].}

proc llStreamOpen(f: File): PLLStream {...}{.raises: [], tags: [].}

proc llStreamOpen(filename: AbsoluteFile; mode: FileMode): PLLStream {...}{.
    raises: [], tags: [].}

proc llStreamOpen(): PLLStream {...}{.raises: [], tags: [].}

proc llStreamOpenStdIn(r: TLLRepl = llReadFromStdin): PLLStream {...}{.raises: [],
    tags: [].}

proc llStreamClose(s: PLLStream) {...}{.raises: [], tags: [].}

proc endsWith(x: string; s: set[char]): bool {...}{.raises: [], tags: [].}

proc endsWithOpr(x: string): bool {...}{.raises: [], tags: [].}

proc llStreamRead(s: PLLStream; buf: pointer; bufLen: int): int {...}{.
    raises: [IOError, Exception], tags: [ReadIOEffect, RootEffect].}

proc llStreamReadLine(s: PLLStream; line: var string): bool {...}{.raises: [IOError],
    tags: [ReadIOEffect].}

proc llStreamWrite(s: PLLStream; data: string) {...}{.raises: [IOError],
    tags: [WriteIOEffect].}

proc llStreamWriteln(s: PLLStream; data: string) {...}{.raises: [IOError],
    tags: [WriteIOEffect].}

proc llStreamWrite(s: PLLStream; data: char) {...}{.raises: [IOError],
    tags: [WriteIOEffect].}

proc llStreamWrite(s: PLLStream; buf: pointer; buflen: int) {...}{.raises: [IOError],
    tags: [WriteIOEffect].}

proc llStreamReadAll(s: PLLStream): string {...}{.raises: [IOError],
    tags: [ReadIOEffect].}