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➡️ Type Caster

Introduction​

The Type Caster library provides functions to simplify non-obvious type castings in Solidity. It supports conversions from static to dynamic arrays, singleton arrays, and arrays of different types.

Functions​

To use the library, you need to import it:

To use the TypeCaster library, you need to import it.

import "@solarity/solidity-lib/libs/utils/TypeCaster.sol";

And optionally bind it to the type with the using statement.

using TypeCaster for *;

asUint256Array​

function asUint256Array(
    bytes32[] memory from_
) internal pure returns (uint256[] memory array_);
function asUint256Array(
    address[] memory from_
) internal pure returns (uint256[] memory array_);

Description​

Converts a from_ array to a uint256 array using assembly. Parameters from_ and returned array_ always a memory array.

Time complexity​

Constant.

Example​

bytes32[] memory bytesArray_ = new bytes32[](2);
bytesArray_[0] = bytes32(0); 
bytesArray_[1] = bytes32(uint256(1));

uint256[] memory intArray_ = bytesArray_.asUint256Array(); // [0, 1]

asAddressArray​

function asAddressArray(
    bytes32[] memory from_
) internal pure returns (address[] memory array_);
function asAddressArray(
    uint256[] memory from_
) internal pure returns (address[] memory array_);

Description​

Converts a from_ array to a address array using assembly. Parameters from_ and returned array_ always a memory array.

Time complexity​

Constant.

Example​

bytes32[] memory bytesArray_ = new bytes32[](2);
bytesArray_[0] = bytes32(0); 
bytesArray_[1] = bytes32(uint256(1));

address[] memory addressArray_ = bytesArray_.asAddressArray(); 
// [address(0), address(1)]

asBytes32Array​

function asBytes32Array(
    uint256[] memory from_
) internal pure returns (bytes32[] memory array_);
function asBytes32Array(
    address[] memory from_
) internal pure returns (bytes32[] memory array_);

Description​

Converts a from_ array to a bytes32 array using assembly. Parameters from_ and returned array_ always a memory array.

Time complexity​

Constant.

Example​

uint256[] memory intArr_ = new uint256[](2);
intArr_[0] = 0; 
intArr_[1] = 1;

bytes32[] memory bytesArr_ = intArr_.asBytes32Array(); // [bytes32(0), bytes32(1)]

asSingletonArray​

function asSingletonArray(
    uint256 from_
) internal pure returns (uint256[] memory array_);
function asSingletonArray(
    address from_
) internal pure returns (address[] memory array_);
function asSingletonArray(
    bool from_
) internal pure returns (bool[] memory array_);
function asSingletonArray(
    string memory from_
) internal pure returns (string[] memory array_);
function asSingletonArray(
    bytes32 from_
) internal pure returns (bytes32[] memory array_);

Description​

Converts a from_ element into a singleton array_. Returned array_ always a memory array.

Time complexity​

Constant.

Example​

uint256 value_ = 1;

uint256[] memory arr_ = value_.asSingletonArray(); // [1]

asDynamic​

function asDynamic(
    uint256[1..5] memory static_
) internal pure returns (uint256[] memory dynamic_);
function asDynamic(
    address[1..5] memory static_
) internal pure returns (address[] memory dynamic_);
function asDynamic(
    bool[1..5] memory static_
) internal pure returns (bool[] memory dynamic_);
function asDynamic(
    string[1..5] memory static_
) internal pure returns (string[] memory dynamic_);
function asDynamic(
    bytes32[1..5] memory static_
) internal pure returns (bytes32[] memory dynamic_);

Description​

Converts a static from_ array into a dynamic_ array. Parameter static_ is always a memory array, as well as dynamic_.

Time complexity​

Linear.

Example​

bool[2] memory staticArray_ = [true, false];

bool[] memory dynamicArray_ = staticArray_.asDynamic(); // [true, false]