ethereum.utils.hexadecimal

Utility Functions For Hexadecimal Strings.

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

Introduction

Hexadecimal strings specific utility functions used in this specification.

has_hex_prefix

Check if a hex string starts with hex prefix (0x).

Parameters

hex_string : The hexadecimal string to be checked for presence of prefix.

Returns

has_prefix : bool Boolean indicating whether the hex string has 0x prefix.

def has_hex_prefix(​hex_string: str​) -> bool:
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    return hex_string.startswith("0x")

remove_hex_prefix

Remove 0x prefix from a hex string if present. This function returns the passed hex string if it isn't prefixed with 0x.

Parameters

hex_string : The hexadecimal string whose prefix is to be removed.

Returns

modified_hex_string : str The hexadecimal string with the 0x prefix removed if present.

def remove_hex_prefix(​hex_string: str​) -> str:
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    if has_hex_prefix(hex_string):
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        return hex_string[len("0x") :]
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    return hex_string

hex_to_bytes

Convert hex string to bytes.

Parameters

hex_string : The hexadecimal string to be converted to bytes.

Returns

byte_stream : bytes Byte stream corresponding to the given hexadecimal string.

def hex_to_bytes(​hex_string: str​) -> Bytes:
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    return Bytes.fromhex(remove_hex_prefix(hex_string))

hex_to_bytes8

Convert hex string to 8 bytes.

Parameters

hex_string : The hexadecimal string to be converted to 8 bytes.

Returns

8_byte_stream : Bytes8 8-byte stream corresponding to the given hexadecimal string.

def hex_to_bytes8(​hex_string: str​) -> Bytes8:
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    return Bytes8(Bytes.fromhex(remove_hex_prefix(hex_string).rjust(16, "0")))

hex_to_bytes32

Convert hex string to 32 bytes.

Parameters

hex_string : The hexadecimal string to be converted to 32 bytes.

Returns

32_byte_stream : Bytes32 32-byte stream corresponding to the given hexadecimal string.

def hex_to_bytes32(​hex_string: str​) -> Bytes32:
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    return Bytes32(Bytes.fromhex(remove_hex_prefix(hex_string).rjust(64, "0")))

hex_to_bytes256

Convert hex string to 256 bytes.

Parameters

hex_string : The hexadecimal string to be converted to 256 bytes.

Returns

256_byte_stream : Bytes256 256-byte stream corresponding to the given hexadecimal string.

def hex_to_bytes256(​hex_string: str​) -> Bytes256:
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    return Bytes256(
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        Bytes.fromhex(remove_hex_prefix(hex_string).rjust(512, "0"))
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    )

hex_to_hash

Convert hex string to hash32 (32 bytes).

Parameters

hex_string : The hexadecimal string to be converted to hash32.

Returns

hash : Hash32 32-byte stream obtained from the given hexadecimal string.

def hex_to_hash(​hex_string: str​) -> Hash32:
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    return Hash32(Bytes.fromhex(remove_hex_prefix(hex_string)))

hex_to_uint

Convert hex string to Uint.

Parameters

hex_string : The hexadecimal string to be converted to Uint.

Returns

converted : Uint The unsigned integer obtained from the given hexadecimal string.

def hex_to_uint(​hex_string: str​) -> Uint:
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    return Uint(int(remove_hex_prefix(hex_string), 16))

hex_to_u8

Convert hex string to U8.

Parameters

hex_string : The hexadecimal string to be converted to U8.

Returns

converted : U8 The U8 integer obtained from the given hexadecimal string.

def hex_to_u8(​hex_string: str​) -> U8:
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    return U8(int(remove_hex_prefix(hex_string), 16))

hex_to_u64

Convert hex string to U64.

Parameters

hex_string : The hexadecimal string to be converted to U64.

Returns

converted : U64 The U64 integer obtained from the given hexadecimal string.

def hex_to_u64(​hex_string: str​) -> U64:
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    return U64(int(remove_hex_prefix(hex_string), 16))

hex_to_u256

Convert hex string to U256.

Parameters

hex_string : The hexadecimal string to be converted to U256.

Returns

converted : U256 The U256 integer obtained from the given hexadecimal string.

def hex_to_u256(​hex_string: str​) -> U256:
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    return U256(int(remove_hex_prefix(hex_string), 16))