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SafeCast

Wrappers over Solidity's uintXX/intXX/bool casting operators with added overflow checks. Downcasting from uint256/int256 in Solidity does not revert on overflow. This can easily result in undesired exploitation or bugs, since developers usually assume that overflows raise errors. SafeCast restores this intuition by reverting the transaction when such an operation overflows. Using this library instead of the unchecked operations eliminates an entire class of bugs, so it's recommended to use it always.

Functions

toUint248

*Returns the downcasted uint248 from uint256, reverting on overflow (when the input is greater than largest uint248). Counterpart to Solidity's uint248 operator. Requirements:

  • input must fit into 248 bits*
function toUint248(uint256 value) internal pure returns (uint248);

toUint240

*Returns the downcasted uint240 from uint256, reverting on overflow (when the input is greater than largest uint240). Counterpart to Solidity's uint240 operator. Requirements:

  • input must fit into 240 bits*
function toUint240(uint256 value) internal pure returns (uint240);

toUint232

*Returns the downcasted uint232 from uint256, reverting on overflow (when the input is greater than largest uint232). Counterpart to Solidity's uint232 operator. Requirements:

  • input must fit into 232 bits*
function toUint232(uint256 value) internal pure returns (uint232);

toUint224

*Returns the downcasted uint224 from uint256, reverting on overflow (when the input is greater than largest uint224). Counterpart to Solidity's uint224 operator. Requirements:

  • input must fit into 224 bits*
function toUint224(uint256 value) internal pure returns (uint224);

toUint216

*Returns the downcasted uint216 from uint256, reverting on overflow (when the input is greater than largest uint216). Counterpart to Solidity's uint216 operator. Requirements:

  • input must fit into 216 bits*
function toUint216(uint256 value) internal pure returns (uint216);

toUint208

*Returns the downcasted uint208 from uint256, reverting on overflow (when the input is greater than largest uint208). Counterpart to Solidity's uint208 operator. Requirements:

  • input must fit into 208 bits*
function toUint208(uint256 value) internal pure returns (uint208);

toUint200

*Returns the downcasted uint200 from uint256, reverting on overflow (when the input is greater than largest uint200). Counterpart to Solidity's uint200 operator. Requirements:

  • input must fit into 200 bits*
function toUint200(uint256 value) internal pure returns (uint200);

toUint192

*Returns the downcasted uint192 from uint256, reverting on overflow (when the input is greater than largest uint192). Counterpart to Solidity's uint192 operator. Requirements:

  • input must fit into 192 bits*
function toUint192(uint256 value) internal pure returns (uint192);

toUint184

*Returns the downcasted uint184 from uint256, reverting on overflow (when the input is greater than largest uint184). Counterpart to Solidity's uint184 operator. Requirements:

  • input must fit into 184 bits*
function toUint184(uint256 value) internal pure returns (uint184);

toUint176

*Returns the downcasted uint176 from uint256, reverting on overflow (when the input is greater than largest uint176). Counterpart to Solidity's uint176 operator. Requirements:

  • input must fit into 176 bits*
function toUint176(uint256 value) internal pure returns (uint176);

toUint168

*Returns the downcasted uint168 from uint256, reverting on overflow (when the input is greater than largest uint168). Counterpart to Solidity's uint168 operator. Requirements:

  • input must fit into 168 bits*
function toUint168(uint256 value) internal pure returns (uint168);

toUint160

*Returns the downcasted uint160 from uint256, reverting on overflow (when the input is greater than largest uint160). Counterpart to Solidity's uint160 operator. Requirements:

  • input must fit into 160 bits*
function toUint160(uint256 value) internal pure returns (uint160);

toUint152

*Returns the downcasted uint152 from uint256, reverting on overflow (when the input is greater than largest uint152). Counterpart to Solidity's uint152 operator. Requirements:

  • input must fit into 152 bits*
function toUint152(uint256 value) internal pure returns (uint152);

toUint144

*Returns the downcasted uint144 from uint256, reverting on overflow (when the input is greater than largest uint144). Counterpart to Solidity's uint144 operator. Requirements:

  • input must fit into 144 bits*
function toUint144(uint256 value) internal pure returns (uint144);

toUint136

*Returns the downcasted uint136 from uint256, reverting on overflow (when the input is greater than largest uint136). Counterpart to Solidity's uint136 operator. Requirements:

  • input must fit into 136 bits*
function toUint136(uint256 value) internal pure returns (uint136);

toUint128

*Returns the downcasted uint128 from uint256, reverting on overflow (when the input is greater than largest uint128). Counterpart to Solidity's uint128 operator. Requirements:

  • input must fit into 128 bits*
function toUint128(uint256 value) internal pure returns (uint128);

toUint120

*Returns the downcasted uint120 from uint256, reverting on overflow (when the input is greater than largest uint120). Counterpart to Solidity's uint120 operator. Requirements:

  • input must fit into 120 bits*
function toUint120(uint256 value) internal pure returns (uint120);

toUint112

*Returns the downcasted uint112 from uint256, reverting on overflow (when the input is greater than largest uint112). Counterpart to Solidity's uint112 operator. Requirements:

  • input must fit into 112 bits*
function toUint112(uint256 value) internal pure returns (uint112);

toUint104

*Returns the downcasted uint104 from uint256, reverting on overflow (when the input is greater than largest uint104). Counterpart to Solidity's uint104 operator. Requirements:

  • input must fit into 104 bits*
function toUint104(uint256 value) internal pure returns (uint104);

toUint96

*Returns the downcasted uint96 from uint256, reverting on overflow (when the input is greater than largest uint96). Counterpart to Solidity's uint96 operator. Requirements:

  • input must fit into 96 bits*
function toUint96(uint256 value) internal pure returns (uint96);

toUint88

*Returns the downcasted uint88 from uint256, reverting on overflow (when the input is greater than largest uint88). Counterpart to Solidity's uint88 operator. Requirements:

  • input must fit into 88 bits*
function toUint88(uint256 value) internal pure returns (uint88);

toUint80

*Returns the downcasted uint80 from uint256, reverting on overflow (when the input is greater than largest uint80). Counterpart to Solidity's uint80 operator. Requirements:

  • input must fit into 80 bits*
function toUint80(uint256 value) internal pure returns (uint80);

toUint72

*Returns the downcasted uint72 from uint256, reverting on overflow (when the input is greater than largest uint72). Counterpart to Solidity's uint72 operator. Requirements:

  • input must fit into 72 bits*
function toUint72(uint256 value) internal pure returns (uint72);

toUint64

*Returns the downcasted uint64 from uint256, reverting on overflow (when the input is greater than largest uint64). Counterpart to Solidity's uint64 operator. Requirements:

  • input must fit into 64 bits*
function toUint64(uint256 value) internal pure returns (uint64);

toUint56

*Returns the downcasted uint56 from uint256, reverting on overflow (when the input is greater than largest uint56). Counterpart to Solidity's uint56 operator. Requirements:

  • input must fit into 56 bits*
function toUint56(uint256 value) internal pure returns (uint56);

toUint48

*Returns the downcasted uint48 from uint256, reverting on overflow (when the input is greater than largest uint48). Counterpart to Solidity's uint48 operator. Requirements:

  • input must fit into 48 bits*
function toUint48(uint256 value) internal pure returns (uint48);

toUint40

*Returns the downcasted uint40 from uint256, reverting on overflow (when the input is greater than largest uint40). Counterpart to Solidity's uint40 operator. Requirements:

  • input must fit into 40 bits*
function toUint40(uint256 value) internal pure returns (uint40);

toUint32

*Returns the downcasted uint32 from uint256, reverting on overflow (when the input is greater than largest uint32). Counterpart to Solidity's uint32 operator. Requirements:

  • input must fit into 32 bits*
function toUint32(uint256 value) internal pure returns (uint32);

toUint24

*Returns the downcasted uint24 from uint256, reverting on overflow (when the input is greater than largest uint24). Counterpart to Solidity's uint24 operator. Requirements:

  • input must fit into 24 bits*
function toUint24(uint256 value) internal pure returns (uint24);

toUint16

*Returns the downcasted uint16 from uint256, reverting on overflow (when the input is greater than largest uint16). Counterpart to Solidity's uint16 operator. Requirements:

  • input must fit into 16 bits*
function toUint16(uint256 value) internal pure returns (uint16);

toUint8

*Returns the downcasted uint8 from uint256, reverting on overflow (when the input is greater than largest uint8). Counterpart to Solidity's uint8 operator. Requirements:

  • input must fit into 8 bits*
function toUint8(uint256 value) internal pure returns (uint8);

toUint256

*Converts a signed int256 into an unsigned uint256. Requirements:

  • input must be greater than or equal to 0.*
function toUint256(int256 value) internal pure returns (uint256);

toInt248

*Returns the downcasted int248 from int256, reverting on overflow (when the input is less than smallest int248 or greater than largest int248). Counterpart to Solidity's int248 operator. Requirements:

  • input must fit into 248 bits*
function toInt248(int256 value) internal pure returns (int248 downcasted);

toInt240

*Returns the downcasted int240 from int256, reverting on overflow (when the input is less than smallest int240 or greater than largest int240). Counterpart to Solidity's int240 operator. Requirements:

  • input must fit into 240 bits*
function toInt240(int256 value) internal pure returns (int240 downcasted);

toInt232

*Returns the downcasted int232 from int256, reverting on overflow (when the input is less than smallest int232 or greater than largest int232). Counterpart to Solidity's int232 operator. Requirements:

  • input must fit into 232 bits*
function toInt232(int256 value) internal pure returns (int232 downcasted);

toInt224

*Returns the downcasted int224 from int256, reverting on overflow (when the input is less than smallest int224 or greater than largest int224). Counterpart to Solidity's int224 operator. Requirements:

  • input must fit into 224 bits*
function toInt224(int256 value) internal pure returns (int224 downcasted);

toInt216

*Returns the downcasted int216 from int256, reverting on overflow (when the input is less than smallest int216 or greater than largest int216). Counterpart to Solidity's int216 operator. Requirements:

  • input must fit into 216 bits*
function toInt216(int256 value) internal pure returns (int216 downcasted);

toInt208

*Returns the downcasted int208 from int256, reverting on overflow (when the input is less than smallest int208 or greater than largest int208). Counterpart to Solidity's int208 operator. Requirements:

  • input must fit into 208 bits*
function toInt208(int256 value) internal pure returns (int208 downcasted);

toInt200

*Returns the downcasted int200 from int256, reverting on overflow (when the input is less than smallest int200 or greater than largest int200). Counterpart to Solidity's int200 operator. Requirements:

  • input must fit into 200 bits*
function toInt200(int256 value) internal pure returns (int200 downcasted);

toInt192

*Returns the downcasted int192 from int256, reverting on overflow (when the input is less than smallest int192 or greater than largest int192). Counterpart to Solidity's int192 operator. Requirements:

  • input must fit into 192 bits*
function toInt192(int256 value) internal pure returns (int192 downcasted);

toInt184

*Returns the downcasted int184 from int256, reverting on overflow (when the input is less than smallest int184 or greater than largest int184). Counterpart to Solidity's int184 operator. Requirements:

  • input must fit into 184 bits*
function toInt184(int256 value) internal pure returns (int184 downcasted);

toInt176

*Returns the downcasted int176 from int256, reverting on overflow (when the input is less than smallest int176 or greater than largest int176). Counterpart to Solidity's int176 operator. Requirements:

  • input must fit into 176 bits*
function toInt176(int256 value) internal pure returns (int176 downcasted);

toInt168

*Returns the downcasted int168 from int256, reverting on overflow (when the input is less than smallest int168 or greater than largest int168). Counterpart to Solidity's int168 operator. Requirements:

  • input must fit into 168 bits*
function toInt168(int256 value) internal pure returns (int168 downcasted);

toInt160

*Returns the downcasted int160 from int256, reverting on overflow (when the input is less than smallest int160 or greater than largest int160). Counterpart to Solidity's int160 operator. Requirements:

  • input must fit into 160 bits*
function toInt160(int256 value) internal pure returns (int160 downcasted);

toInt152

*Returns the downcasted int152 from int256, reverting on overflow (when the input is less than smallest int152 or greater than largest int152). Counterpart to Solidity's int152 operator. Requirements:

  • input must fit into 152 bits*
function toInt152(int256 value) internal pure returns (int152 downcasted);

toInt144

*Returns the downcasted int144 from int256, reverting on overflow (when the input is less than smallest int144 or greater than largest int144). Counterpart to Solidity's int144 operator. Requirements:

  • input must fit into 144 bits*
function toInt144(int256 value) internal pure returns (int144 downcasted);

toInt136

*Returns the downcasted int136 from int256, reverting on overflow (when the input is less than smallest int136 or greater than largest int136). Counterpart to Solidity's int136 operator. Requirements:

  • input must fit into 136 bits*
function toInt136(int256 value) internal pure returns (int136 downcasted);

toInt128

*Returns the downcasted int128 from int256, reverting on overflow (when the input is less than smallest int128 or greater than largest int128). Counterpart to Solidity's int128 operator. Requirements:

  • input must fit into 128 bits*
function toInt128(int256 value) internal pure returns (int128 downcasted);

toInt120

*Returns the downcasted int120 from int256, reverting on overflow (when the input is less than smallest int120 or greater than largest int120). Counterpart to Solidity's int120 operator. Requirements:

  • input must fit into 120 bits*
function toInt120(int256 value) internal pure returns (int120 downcasted);

toInt112

*Returns the downcasted int112 from int256, reverting on overflow (when the input is less than smallest int112 or greater than largest int112). Counterpart to Solidity's int112 operator. Requirements:

  • input must fit into 112 bits*
function toInt112(int256 value) internal pure returns (int112 downcasted);

toInt104

*Returns the downcasted int104 from int256, reverting on overflow (when the input is less than smallest int104 or greater than largest int104). Counterpart to Solidity's int104 operator. Requirements:

  • input must fit into 104 bits*
function toInt104(int256 value) internal pure returns (int104 downcasted);

toInt96

*Returns the downcasted int96 from int256, reverting on overflow (when the input is less than smallest int96 or greater than largest int96). Counterpart to Solidity's int96 operator. Requirements:

  • input must fit into 96 bits*
function toInt96(int256 value) internal pure returns (int96 downcasted);

toInt88

*Returns the downcasted int88 from int256, reverting on overflow (when the input is less than smallest int88 or greater than largest int88). Counterpart to Solidity's int88 operator. Requirements:

  • input must fit into 88 bits*
function toInt88(int256 value) internal pure returns (int88 downcasted);

toInt80

*Returns the downcasted int80 from int256, reverting on overflow (when the input is less than smallest int80 or greater than largest int80). Counterpart to Solidity's int80 operator. Requirements:

  • input must fit into 80 bits*
function toInt80(int256 value) internal pure returns (int80 downcasted);

toInt72

*Returns the downcasted int72 from int256, reverting on overflow (when the input is less than smallest int72 or greater than largest int72). Counterpart to Solidity's int72 operator. Requirements:

  • input must fit into 72 bits*
function toInt72(int256 value) internal pure returns (int72 downcasted);

toInt64

*Returns the downcasted int64 from int256, reverting on overflow (when the input is less than smallest int64 or greater than largest int64). Counterpart to Solidity's int64 operator. Requirements:

  • input must fit into 64 bits*
function toInt64(int256 value) internal pure returns (int64 downcasted);

toInt56

*Returns the downcasted int56 from int256, reverting on overflow (when the input is less than smallest int56 or greater than largest int56). Counterpart to Solidity's int56 operator. Requirements:

  • input must fit into 56 bits*
function toInt56(int256 value) internal pure returns (int56 downcasted);

toInt48

*Returns the downcasted int48 from int256, reverting on overflow (when the input is less than smallest int48 or greater than largest int48). Counterpart to Solidity's int48 operator. Requirements:

  • input must fit into 48 bits*
function toInt48(int256 value) internal pure returns (int48 downcasted);

toInt40

*Returns the downcasted int40 from int256, reverting on overflow (when the input is less than smallest int40 or greater than largest int40). Counterpart to Solidity's int40 operator. Requirements:

  • input must fit into 40 bits*
function toInt40(int256 value) internal pure returns (int40 downcasted);

toInt32

*Returns the downcasted int32 from int256, reverting on overflow (when the input is less than smallest int32 or greater than largest int32). Counterpart to Solidity's int32 operator. Requirements:

  • input must fit into 32 bits*
function toInt32(int256 value) internal pure returns (int32 downcasted);

toInt24

*Returns the downcasted int24 from int256, reverting on overflow (when the input is less than smallest int24 or greater than largest int24). Counterpart to Solidity's int24 operator. Requirements:

  • input must fit into 24 bits*
function toInt24(int256 value) internal pure returns (int24 downcasted);

toInt16

*Returns the downcasted int16 from int256, reverting on overflow (when the input is less than smallest int16 or greater than largest int16). Counterpart to Solidity's int16 operator. Requirements:

  • input must fit into 16 bits*
function toInt16(int256 value) internal pure returns (int16 downcasted);

toInt8

*Returns the downcasted int8 from int256, reverting on overflow (when the input is less than smallest int8 or greater than largest int8). Counterpart to Solidity's int8 operator. Requirements:

  • input must fit into 8 bits*
function toInt8(int256 value) internal pure returns (int8 downcasted);

toInt256

*Converts an unsigned uint256 into a signed int256. Requirements:

  • input must be less than or equal to maxInt256.*
function toInt256(uint256 value) internal pure returns (int256);

toUint

Cast a boolean (false or true) to a uint256 (0 or 1) with no jump.

function toUint(bool b) internal pure returns (uint256 u);

Errors

SafeCastOverflowedUintDowncast

Value doesn't fit in an uint of bits size.

error SafeCastOverflowedUintDowncast(uint8 bits, uint256 value);

SafeCastOverflowedIntToUint

An int value doesn't fit in an uint of bits size.

error SafeCastOverflowedIntToUint(int256 value);

SafeCastOverflowedIntDowncast

Value doesn't fit in an int of bits size.

error SafeCastOverflowedIntDowncast(uint8 bits, int256 value);

SafeCastOverflowedUintToInt

An uint value doesn't fit in an int of bits size.

error SafeCastOverflowedUintToInt(uint256 value);