ethereum.utils.safe_arithmetic

Safe Arithmetic for U256 Integer Type ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. contents:: Table of Contents :backlinks: none :local:

Introduction

Safe arithmetic utility functions for U256 integer type.

u256_safe_add

Adds together the given sequence of numbers. If the total sum of the numbers exceeds U256.MAX_VALUE then an exception is raised. If exception_type = None then the exception raised defaults to the one raised by U256 when U256.value > U256.MAX_VALUE else exception_type is raised.

Parameters

numbers : The sequence of numbers that need to be added together.

exception_type: The exception that needs to be raised if the sum of the numbers exceeds U256.MAX_VALUE.

Returns

result : ethereum.base_types.U256 The sum of the given sequence of numbers if the total is less than U256.MAX_VALUE else an exception is raised. If exception_type = None then the exception raised defaults to the one raised by U256 when U256.value > U256.MAX_VALUE else exception_type is raised.

def u256_safe_add(​*numbers: Union[U256, Uint], ​​exception_type: Optional[Type[BaseException]]​) -> U256:
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    """
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    Adds together the given sequence of numbers. If the total sum of the
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    numbers exceeds `U256.MAX_VALUE` then an exception is raised.
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    If `exception_type` = None then the exception raised defaults to the one
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    raised by `U256` when `U256.value > U256.MAX_VALUE`
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    else `exception_type` is raised.
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    Parameters
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    ----------
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    numbers :
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        The sequence of numbers that need to be added together.
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    exception_type:
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        The exception that needs to be raised if the sum of the `numbers`
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        exceeds `U256.MAX_VALUE`.
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    Returns
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    -------
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    result : `ethereum.base_types.U256`
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        The sum of the given sequence of numbers if the total is less than
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        `U256.MAX_VALUE` else an exception is raised.
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        If `exception_type` = None then the exception raised defaults to the
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        one raised by `U256` when `U256.value > U256.MAX_VALUE`
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        else `exception_type` is raised.
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    """
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    try:
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        return U256(sum(numbers))
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    except ValueError as e:
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        if exception_type:
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            raise exception_type from e
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        else:
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            raise e

u256_safe_multiply

Multiplies together the given sequence of numbers. If the net product of the numbers exceeds U256.MAX_VALUE then an exception is raised. If exception_type = None then the exception raised defaults to the one raised by U256 when U256.value > U256.MAX_VALUE else exception_type is raised.

Parameters

numbers : The sequence of numbers that need to be multiplies together.

exception_type: The exception that needs to be raised if the sum of the numbers exceeds U256.MAX_VALUE.

Returns

result : ethereum.base_types.U256 The multiplication product of the given sequence of numbers if the net product is less than U256.MAX_VALUE else an exception is raised. If exception_type = None then the exception raised defaults to the one raised by U256 when U256.value > U256.MAX_VALUE else exception_type is raised.

def u256_safe_multiply(​*numbers: Union[U256, Uint], ​​exception_type: Optional[Type[BaseException]]​) -> U256:
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    """
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    Multiplies together the given sequence of numbers. If the net product of
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    the numbers exceeds `U256.MAX_VALUE` then an exception is raised.
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    If `exception_type` = None then the exception raised defaults to the one
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    raised by `U256` when `U256.value > U256.MAX_VALUE` else
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    `exception_type` is raised.
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    Parameters
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    ----------
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    numbers :
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        The sequence of numbers that need to be multiplies together.
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    exception_type:
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        The exception that needs to be raised if the sum of the `numbers`
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        exceeds `U256.MAX_VALUE`.
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    Returns
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    -------
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    result : `ethereum.base_types.U256`
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        The multiplication product of the given sequence of numbers if the
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        net product  is less than `U256.MAX_VALUE` else an exception is raised.
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        If `exception_type` = None then the exception raised defaults to the
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        one raised by `U256` when `U256.value > U256.MAX_VALUE`
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        else `exception_type` is raised.
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    """
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    result = numbers[0]
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    try:
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        for number in numbers[1:]:
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            result *= number
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        return U256(result)
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    except ValueError as e:
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        if exception_type:
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            raise exception_type from e
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        else:
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            raise e