dramaticlly commented on a change in pull request #4262: URL: https://github.com/apache/iceberg/pull/4262#discussion_r837057414
########## File path: python/src/iceberg/expression/literals.py ########## @@ -0,0 +1,502 @@ +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, +# software distributed under the License is distributed on an +# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +# KIND, either express or implied. See the License for the +# specific language governing permissions and limitations +# under the License. + +import datetime +import struct +import sys +import uuid +from abc import ABC, abstractmethod +from decimal import ROUND_HALF_UP, Decimal +from functools import singledispatch +from typing import Generic, Optional, TypeVar, Union + +if sys.version_info >= (3, 8): + from functools import singledispatchmethod # pragma: no cover +else: + from singledispatch import singledispatchmethod # pragma: no cover + +import pytz + +from iceberg.types import ( + BinaryType, + BooleanType, + DateType, + DecimalType, + DoubleType, + FixedType, + FloatType, + IntegerType, + LongType, + Singleton, + StringType, + TimestampType, + TimestamptzType, + TimeType, + UUIDType, +) + +EPOCH = datetime.datetime.utcfromtimestamp(0) +T = TypeVar("T") + + +class Literal(Generic[T], ABC): + """Literal which has a value and can be converted between types""" + + def __init__(self, value: T): + if value is None: + raise TypeError(f"Invalid literal value: {value}") + self._value = value + + @property + def value(self) -> T: + return self._value + + @abstractmethod + def to(self, type_var): + ... # pragma: no cover + + def __repr__(self): + return f"{type(self).__name__}({self.value})" + + def __str__(self): + return str(self.value) + + def __eq__(self, other): + return self.value == other.value + + def __ne__(self, other): + return not self.__eq__(other) + + def __lt__(self, other): + return self.value < other.value + + def __gt__(self, other): + return self.value > other.value + + def __le__(self, other): + return self.value <= other.value + + def __ge__(self, other): + return self.value >= other.value + + +@singledispatch +def literal(value) -> Literal: + """ + A generic Literal factory to construct an iceberg Literal based on python primitive data type + using dynamic overloading + + Args: + value(python primitive type): the value to be associated with literal + + Example: + from iceberg.expressions.literals import literal + >>> literal(123) + IntegerLiteral(123) + """ + raise TypeError(f"Unimplemented Type Literal for value: {str(value)}") Review comment: hey sorry, not sure if I followed your thought on this. this `literal` is the factory method which take the python primitive value and then convert to the iceberg Literal. I feel as the base method of singledispatch, it does not have the access to the concrete instance of parametrized Literal, so I am not sure if we can use `repr` here. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
