Class whose attributes can by references to other attributes
Source code in quam/utils/reference_class.py
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105 | class ReferenceClass:
"""Class whose attributes can by references to other attributes"""
_initialized: ClassVar[bool] = False
def __post_init__(self) -> None:
"""Post init function"""
self._initialized = True
def _get_referenced_value(self, attr: str) -> Any:
"""Get the value of an attribute by reference
This function should generally be overwritten by subclasses
"""
raise NotImplementedError
def _is_reference(self, attr: str) -> bool:
"""Check if an attribute is a reference
This function should generally be overwritten by subclasses
"""
raise NotImplementedError
def get_unreferenced_value(self, attr: str) -> bool:
"""Check if an attribute is a reference"""
return super().__getattribute__(attr)
def __getattribute__(self, attr: str) -> Any:
attr_val = super().__getattribute__(attr)
if attr in ["_is_reference", "_get_referenced_value", "__post_init__"]:
return attr_val
try:
if self._is_reference(attr_val):
return self._get_referenced_value(attr_val)
return attr_val
except Exception:
return attr_val
def _is_valid_setattr(
self, attr: str, value: Any, error_on_False: bool = False
) -> bool:
"""Check if an attribute can be set to a value
This will be called by __setattr__ to check if the attribute can be set to the
given value.
Args:
attr: The attribute to set
value: The value to set the attribute to
error_on_False: If True, raise an error if the attribute cannot be set to
the value. If False, return False if the attribute cannot be set to the
value.
Returns:
True if
- The new value is None
- The attribute does not exist yet
- The attribute's previous value is not a reference
- The new value is a reference
False otherwise, in particular if the previous value is a reference and the
new value is not and is also not None.
Raises:
ValueError: If error_on_False is True and the attribute cannot be set to
the value.
"""
if value is None:
return True
try:
original_value = self.get_unreferenced_value(attr)
except AttributeError:
return True
if not self._initialized:
return True
if self._is_reference(original_value):
if self._is_reference(value):
return True
if not error_on_False:
return False
raise ValueError(
f"Cannot set attribute {attr} to {value} because it is a reference. "
"To overwrite the reference, set the attribute to None first.\n"
f"Object: {self}\n"
f"Original value: {original_value}"
)
return True
def __setattr__(self, attr: str, value: Any) -> None:
self._is_valid_setattr(attr, value, error_on_False=True)
super().__setattr__(attr, value)
|
__post_init__()
Post init function
Source code in quam/utils/reference_class.py
| def __post_init__(self) -> None:
"""Post init function"""
self._initialized = True
|
get_unreferenced_value(attr)
Check if an attribute is a reference
Source code in quam/utils/reference_class.py
| def get_unreferenced_value(self, attr: str) -> bool:
"""Check if an attribute is a reference"""
return super().__getattribute__(attr)
|