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Result - represents outcome. Avoid propagating exceptions.
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class Result: | |
"""Represents the outcome/result of an operation. Use instead of propogating exceptions | |
accross layers. Use exceptions for only exceptional cases. | |
Attributes | |
---------- | |
success : bool | |
A flag that is set to True if the operation was successful, False if | |
the operation failed. | |
value : object | |
The result of the operation if successful, value is None if operation | |
failed or if the operation has no return value. | |
error : object | |
Error detailing why the operation failed, value is None if | |
operation was successful. | |
Usage | |
----- | |
def handler() -> Result | |
if response.status_code == 200: | |
return Result.Success(value="dummy value") | |
else: | |
return Result.Error(error="dummy error") | |
def caller(): | |
result = handler() | |
if result: | |
print(f"Success: {result.value}") | |
else: | |
print(f"Error: {result.error}") | |
""" | |
def __init__(self, success, value, error): | |
self.success = success | |
self.error = error | |
self.value = value | |
def __bool__(self): | |
return self.success | |
@classmethod | |
def Error(cls, error=None): | |
return cls(False, value=None, error=error) | |
@classmethod | |
def Success(cls, value=None): | |
return cls(True, value=value, error=None) |
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