def join_maybe(self, err: str) -> 'IO[B]':
def f(a: Union[A, Maybe[B]]) -> 'IO[B]':
return (IO.from_maybe(a, err) if isinstance(a, Maybe) else
IO.failed(f'`IO.join_maybe` called on {self}'))
return self.flat_map(f,
fs=Just(Eval.later('join_maybe({})'.format, err)))
def flat_map(self,
f: Callable[[A], 'IO[B]'],
ts: Maybe[Eval[str]] = Nothing,
fs: Maybe[Eval[str]] = Nothing) -> 'IO[B]':
ts1 = ts | self.lambda_str
fs1 = fs | Eval.later(lambda: f'flat_map({lambda_str(f)})')
return self._flat_map(f, ts1, fs1)
def safe_fmt(f: Callable[..., Any], a: tuple, kw: dict) -> Eval[str]:
def s() -> str:
try:
return format_funcall(f, Lists.wrap(a), kw)
except Exception as e:
return str(f)
log.error(str(e))
return Eval.later(s)
def lambda_str(self) -> Eval[str]:
return Eval.later(lambda: f'Pure({self.value})')
def and_then(self, nxt: 'IO[B]') -> 'IO[B]':
fs = Eval.later(lambda: 'and_then({nxt.lambda_str()})')
return self.flat_map(lambda a: nxt, fs=Just(fs))