mirror of
https://github.com/erg-lang/erg.git
synced 2025-09-29 04:24:43 +00:00
18 lines
450 B
Python
18 lines
450 B
Python
from typing import TypeVar, Union, _SpecialForm, _type_check
|
|
|
|
class Error:
|
|
def __init__(self, message):
|
|
self.message = message
|
|
|
|
T = TypeVar("T")
|
|
@_SpecialForm
|
|
def Result(self, parameters):
|
|
"""Result type.
|
|
|
|
Result[T] is equivalent to Union[T, Error].
|
|
"""
|
|
arg = _type_check(parameters, f"{self} requires a single type.")
|
|
return Union[arg, Error]
|
|
|
|
def is_ok(obj: Result[T]) -> bool:
|
|
return not isinstance(obj, Error)
|