harn-stdlib 0.8.12

Embedded Harn standard library source catalog
Documentation 
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/** std/io - interactive terminal input and stderr helpers. */
type ReadLineOptions = {prompt?: string, timeout_ms?: int, trim?: bool, echo?: bool, raw?: bool}

type ReadLineResult = {ok: bool, value?: string, status?: string, error?: string}

/** is_tty returns whether fd 0, 1, or 2 is attached to a terminal. */
pub fn is_tty(fd: int = 0) -> bool {
  if fd == 0 {
    return is_stdin_tty()
  }
  if fd == 1 {
    return is_stdout_tty()
  }
  if fd == 2 {
    return is_stderr_tty()
  }
  throw "std/io.is_tty: fd must be 0, 1, or 2"
}

/** read_line reads one line from stdin and reports ok/eof/timeout/interrupt/error. */
pub fn read_line(opts: ReadLineOptions = {}) -> ReadLineResult {
  return __io_read_line(opts ?? {})
}

/** read_password reads one line with terminal echo disabled. */
pub fn read_password(prompt: string = "", timeout_ms: int? = nil) -> ReadLineResult {
  return read_line({prompt: prompt, timeout_ms: timeout_ms, echo: false})
}

/** write_stderr writes text to stderr without appending a newline. */
pub fn write_stderr(text: string) {
  eprint(text)
}