// SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v5.6.0) (utils/Arrays.sol) // This file was procedurally generated from scripts/generate/templates/Arrays.js. pragma solidity ^0.8.24; import {Comparators} from "./Comparators.sol"; import {SlotDerivation} from "./SlotDerivation.sol"; import {StorageSlot} from "./StorageSlot.sol"; import {Math} from "./math/Math.sol"; /** * @dev Collection of functions related to array types. */ library Arrays { using SlotDerivation for bytes32; using StorageSlot for bytes32; /** * @dev Sort an array of uint256 (in memory) following the provided comparator function. * * This function does the sorting "in place", meaning that it overrides the input. The object is returned for * convenience, but that returned value can be discarded safely if the caller has a memory pointer to the array. * * NOTE: this function's cost is `O(n · log(n))` in average and `O(n²)` in the worst case, with n the length of the * array. Using it in view functions that are executed through `eth_call` is safe, but one should be very careful * when executing this as part of a transaction. If the array being sorted is too large, the sort operation may * consume more gas than is available in a block, leading to potential DoS. * * IMPORTANT: Consider memory side-effects when using custom comparator functions that access memory in an unsafe way. */ function sort( uint256[] memory array, function(uint256, uint256) pure returns (bool) comp ) internal pure returns (uint256[] memory) { _quickSort(_begin(array), _end(array), comp); return array; } /** * @dev Variant of {sort} that sorts an array of uint256 in increasing order. */ function sort(uint256[] memory array) internal pure returns (uint256[] memory) { sort(array, Comparators.lt); return array; } /** * @dev Sort an array of address (in memory) following the provided comparator function. * * This function does the sorting "in place", meaning that it overrides the input. The object is returned for * convenience, but that returned value can be discarded safely if the caller has a memory pointer to the array. * * NOTE: this function's cost is `O(n · log(n))` in average and `O(n²)` in the worst case, with n the length of the * array. Using it in view functions that are executed through `eth_call` is safe, but one should be very careful * when executing this as part of a transaction. If the array being sorted is too large, the sort operation may * consume more gas than is available in a block, leading to potential DoS. * * IMPORTANT: Consider memory side-effects when using custom comparator functions that access memory in an unsafe way. */ function sort( address[] memory array, function(address, address) pure returns (bool) comp ) internal pure returns (address[] memory) { sort(_castToUint256Array(array), _castToUint256Comp(comp)); return array; } /** * @dev Variant of {sort} that sorts an array of address in increasing order. */ function sort(address[] memory array) internal pure returns (address[] memory) { sort(_castToUint256Array(array), Comparators.lt); return array; } /** * @dev Sort an array of bytes32 (in memory) following the provided comparator function. * * This function does the sorting "in place", meaning that it overrides the input. The object is returned for * convenience, but that returned value can be discarded safely if the caller has a memory pointer to the array. * * NOTE: this function's cost is `O(n · log(n))` in average and `O(n²)` in the worst case, with n the length of the * array. Using it in view functions that are executed through `eth_call` is safe, but one should be very careful * when executing this as part of a transaction. If the array being sorted is too large, the sort operation may * consume more gas than is available in a block, leading to potential DoS. * * IMPORTANT: Consider memory side-effects when using custom comparator functions that access memory in an unsafe way. */ function sort( bytes32[] memory array, function(bytes32, bytes32) pure returns (bool) comp ) internal pure returns (bytes32[] memory) { sort(_castToUint256Array(array), _castToUint256Comp(comp)); return array; } /** * @dev Variant of {sort} that sorts an array of bytes32 in increasing order. */ function sort(bytes32[] memory array) internal pure returns (bytes32[] memory) { sort(_castToUint256Array(array), Comparators.lt); return array; } /** * @dev Performs a quick sort of a segment of memory. The segment sorted starts at `begin` (inclusive), and stops * at end (exclusive). Sorting follows the `comp` comparator. * * Invariant: `begin <= end`. This is the case when initially called by {sort} and is preserved in subcalls. * * IMPORTANT: Memory locations between `begin` and `end` are not validated/zeroed. This function should * be used only if the limits are within a memory array. */ function _quickSort(uint256 begin, uint256 end, function(uint256, uint256) pure returns (bool) comp) private pure { unchecked { if (end - begin < 0x40) return; // Use first element as pivot uint256 pivot = _mload(begin); // Position where the pivot should be at the end of the loop uint256 pos = begin; for (uint256 it = begin + 0x20; it < end; it += 0x20) { if (comp(_mload(it), pivot)) { // If the value stored at the iterator's position comes before the pivot, we increment the // position of the pivot and move the value there. pos += 0x20; _swap(pos, it); } } _swap(begin, pos); // Swap pivot into place _quickSort(begin, pos, comp); // Sort the left side of the pivot _quickSort(pos + 0x20, end, comp); // Sort the right side of the pivot } } /** * @dev Pointer to the memory location of the first element of `array`. */ function _begin(uint256[] memory array) private pure returns (uint256 ptr) { assembly ("memory-safe") { ptr := add(array, 0x20) } } /** * @dev Pointer to the memory location of the first memory word (32bytes) after `array`. This is the memory word * that comes just after the last element of the array. */ function _end(uint256[] memory array) private pure returns (uint256 ptr) { unchecked { return _begin(array) + array.length * 0x20; } } /** * @dev Load memory word (as a uint256) at location `ptr`. */ function _mload(uint256 ptr) private pure returns (uint256 value) { assembly { value := mload(ptr) } } /** * @dev Swaps the elements memory location `ptr1` and `ptr2`. */ function _swap(uint256 ptr1, uint256 ptr2) private pure { assembly { let value1 := mload(ptr1) let value2 := mload(ptr2) mstore(ptr1, value2) mstore(ptr2, value1) } } /// @dev Helper: low level cast address memory array to uint256 memory array function _castToUint256Array(address[] memory input) private pure returns (uint256[] memory output) { assembly { output := input } } /// @dev Helper: low level cast bytes32 memory array to uint256 memory array function _castToUint256Array(bytes32[] memory input) private pure returns (uint256[] memory output) { assembly { output := input } } /// @dev Helper: low level cast address comp function to uint256 comp function function _castToUint256Comp( function(address, address) pure returns (bool) input ) private pure returns (function(uint256, uint256) pure returns (bool) output) { assembly { output := input } } /// @dev Helper: low level cast bytes32 comp function to uint256 comp function function _castToUint256Comp( function(bytes32, bytes32) pure returns (bool) input ) private pure returns (function(uint256, uint256) pure returns (bool) output) { assembly { output := input } } /** * @dev Searches a sorted `array` and returns the first index that contains * a value greater or equal to `element`. If no such index exists (i.e. all * values in the array are strictly less than `element`), the array length is * returned. Time complexity O(log n). * * NOTE: The `array` is expected to be sorted in ascending order, and to * contain no repeated elements. * * IMPORTANT: Deprecated. This implementation behaves as {lowerBound} but lacks * support for repeated elements in the array. The {lowerBound} function should * be used instead. */ function findUpperBound(uint256[] storage array, uint256 element) internal view returns (uint256) { uint256 low = 0; uint256 high = array.length; if (high == 0) { return 0; } while (low < high) { uint256 mid = Math.average(low, high); // Note that mid will always be strictly less than high (i.e. it will be a valid array index) // because Math.average rounds towards zero (it does integer division with truncation). if (unsafeAccess(array, mid).value > element) { high = mid; } else { low = mid + 1; } } // At this point `low` is the exclusive upper bound. We will return the inclusive upper bound. if (low > 0 && unsafeAccess(array, low - 1).value == element) { return low - 1; } else { return low; } } /** * @dev Searches an `array` sorted in ascending order and returns the first * index that contains a value greater or equal than `element`. If no such index * exists (i.e. all values in the array are strictly less than `element`), the array * length is returned. Time complexity O(log n). * * See C++'s https://en.cppreference.com/w/cpp/algorithm/lower_bound[lower_bound]. */ function lowerBound(uint256[] storage array, uint256 element) internal view returns (uint256) { uint256 low = 0; uint256 high = array.length; if (high == 0) { return 0; } while (low < high) { uint256 mid = Math.average(low, high); // Note that mid will always be strictly less than high (i.e. it will be a valid array index) // because Math.average rounds towards zero (it does integer division with truncation). if (unsafeAccess(array, mid).value < element) { // this cannot overflow because mid < high unchecked { low = mid + 1; } } else { high = mid; } } return low; } /** * @dev Searches an `array` sorted in ascending order and returns the first * index that contains a value strictly greater than `element`. If no such index * exists (i.e. all values in the array are strictly less than `element`), the array * length is returned. Time complexity O(log n). * * See C++'s https://en.cppreference.com/w/cpp/algorithm/upper_bound[upper_bound]. */ function upperBound(uint256[] storage array, uint256 element) internal view returns (uint256) { uint256 low = 0; uint256 high = array.length; if (high == 0) { return 0; } while (low < high) { uint256 mid = Math.average(low, high); // Note that mid will always be strictly less than high (i.e. it will be a valid array index) // because Math.average rounds towards zero (it does integer division with truncation). if (unsafeAccess(array, mid).value > element) { high = mid; } else { // this cannot overflow because mid < high unchecked { low = mid + 1; } } } return low; } /** * @dev Same as {lowerBound}, but with an array in memory. */ function lowerBoundMemory(uint256[] memory array, uint256 element) internal pure returns (uint256) { uint256 low = 0; uint256 high = array.length; if (high == 0) { return 0; } while (low < high) { uint256 mid = Math.average(low, high); // Note that mid will always be strictly less than high (i.e. it will be a valid array index) // because Math.average rounds towards zero (it does integer division with truncation). if (unsafeMemoryAccess(array, mid) < element) { // this cannot overflow because mid < high unchecked { low = mid + 1; } } else { high = mid; } } return low; } /** * @dev Same as {upperBound}, but with an array in memory. */ function upperBoundMemory(uint256[] memory array, uint256 element) internal pure returns (uint256) { uint256 low = 0; uint256 high = array.length; if (high == 0) { return 0; } while (low < high) { uint256 mid = Math.average(low, high); // Note that mid will always be strictly less than high (i.e. it will be a valid array index) // because Math.average rounds towards zero (it does integer division with truncation). if (unsafeMemoryAccess(array, mid) > element) { high = mid; } else { // this cannot overflow because mid < high unchecked { low = mid + 1; } } } return low; } /** * @dev Copies the content of `array`, from `start` (included) to the end of `array` into a new address array in * memory. * * NOTE: replicates the behavior of https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/slice[Javascript's `Array.slice`] */ function slice(address[] memory array, uint256 start) internal pure returns (address[] memory) { return slice(array, start, array.length); } /** * @dev Copies the content of `array`, from `start` (included) to `end` (excluded) into a new address array in * memory. The `end` argument is truncated to the length of the `array`. * * NOTE: replicates the behavior of https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/slice[Javascript's `Array.slice`] */ function slice(address[] memory array, uint256 start, uint256 end) internal pure returns (address[] memory) { // sanitize end = Math.min(end, array.length); start = Math.min(start, end); // allocate and copy address[] memory result = new address[](end - start); assembly ("memory-safe") { mcopy(add(result, 0x20), add(add(array, 0x20), mul(start, 0x20)), mul(sub(end, start), 0x20)) } return result; } /** * @dev Copies the content of `array`, from `start` (included) to the end of `array` into a new bytes32 array in * memory. * * NOTE: replicates the behavior of https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/slice[Javascript's `Array.slice`] */ function slice(bytes32[] memory array, uint256 start) internal pure returns (bytes32[] memory) { return slice(array, start, array.length); } /** * @dev Copies the content of `array`, from `start` (included) to `end` (excluded) into a new bytes32 array in * memory. The `end` argument is truncated to the length of the `array`. * * NOTE: replicates the behavior of https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/slice[Javascript's `Array.slice`] */ function slice(bytes32[] memory array, uint256 start, uint256 end) internal pure returns (bytes32[] memory) { // sanitize end = Math.min(end, array.length); start = Math.min(start, end); // allocate and copy bytes32[] memory result = new bytes32[](end - start); assembly ("memory-safe") { mcopy(add(result, 0x20), add(add(array, 0x20), mul(start, 0x20)), mul(sub(end, start), 0x20)) } return result; } /** * @dev Copies the content of `array`, from `start` (included) to the end of `array` into a new uint256 array in * memory. * * NOTE: replicates the behavior of https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/slice[Javascript's `Array.slice`] */ function slice(uint256[] memory array, uint256 start) internal pure returns (uint256[] memory) { return slice(array, start, array.length); } /** * @dev Copies the content of `array`, from `start` (included) to `end` (excluded) into a new uint256 array in * memory. The `end` argument is truncated to the length of the `array`. * * NOTE: replicates the behavior of https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/slice[Javascript's `Array.slice`] */ function slice(uint256[] memory array, uint256 start, uint256 end) internal pure returns (uint256[] memory) { // sanitize end = Math.min(end, array.length); start = Math.min(start, end); // allocate and copy uint256[] memory result = new uint256[](end - start); assembly ("memory-safe") { mcopy(add(result, 0x20), add(add(array, 0x20), mul(start, 0x20)), mul(sub(end, start), 0x20)) } return result; } /** * @dev Moves the content of `array`, from `start` (included) to the end of `array` to the start of that array, * and shrinks the array length accordingly, effectively overwriting the array with array[start:]. * * NOTE: This function modifies the provided array in place. If you need to preserve the original array, use {slice} instead. */ function splice(address[] memory array, uint256 start) internal pure returns (address[] memory) { return splice(array, start, array.length); } /** * @dev Moves the content of `array`, from `start` (included) to `end` (excluded) to the start of that array, * and shrinks the array length accordingly, effectively overwriting the array with array[start:end]. The * `end` argument is truncated to the length of the `array`. * * NOTE: This function modifies the provided array in place. If you need to preserve the original array, use {slice} instead. */ function splice(address[] memory array, uint256 start, uint256 end) internal pure returns (address[] memory) { // sanitize end = Math.min(end, array.length); start = Math.min(start, end); // move and resize assembly ("memory-safe") { mcopy(add(array, 0x20), add(add(array, 0x20), mul(start, 0x20)), mul(sub(end, start), 0x20)) mstore(array, sub(end, start)) } return array; } /** * @dev Replaces elements in `array` starting at `pos` with all elements from `replacement`. * * Parameters are clamped to valid ranges (e.g. `pos` is clamped to `[0, array.length]`). * If `pos >= array.length`, no replacement occurs and the array is returned unchanged. * * NOTE: This function modifies the provided array in place. */ function replace( address[] memory array, uint256 pos, address[] memory replacement ) internal pure returns (address[] memory) { return replace(array, pos, replacement, 0, replacement.length); } /** * @dev Replaces elements in `array` starting at `pos` with elements from `replacement` starting at `offset`. * Copies at most `length` elements from `replacement` to `array`. * * Parameters are clamped to valid ranges (i.e. `pos` is clamped to `[0, array.length]`, `offset` is * clamped to `[0, replacement.length]`, and `length` is clamped to `min(length, replacement.length - offset, * array.length - pos)`). If `pos >= array.length` or `offset >= replacement.length`, no replacement occurs * and the array is returned unchanged. * * NOTE: This function modifies the provided array in place. */ function replace( address[] memory array, uint256 pos, address[] memory replacement, uint256 offset, uint256 length ) internal pure returns (address[] memory) { // sanitize pos = Math.min(pos, array.length); offset = Math.min(offset, replacement.length); length = Math.min(length, Math.min(replacement.length - offset, array.length - pos)); // replace assembly ("memory-safe") { mcopy( add(add(array, 0x20), mul(pos, 0x20)), add(add(replacement, 0x20), mul(offset, 0x20)), mul(length, 0x20) ) } return array; } /** * @dev Moves the content of `array`, from `start` (included) to the end of `array` to the start of that array, * and shrinks the array length accordingly, effectively overwriting the array with array[start:]. * * NOTE: This function modifies the provided array in place. If you need to preserve the original array, use {slice} instead. */ function splice(bytes32[] memory array, uint256 start) internal pure returns (bytes32[] memory) { return splice(array, start, array.length); } /** * @dev Moves the content of `array`, from `start` (included) to `end` (excluded) to the start of that array, * and shrinks the array length accordingly, effectively overwriting the array with array[start:end]. The * `end` argument is truncated to the length of the `array`. * * NOTE: This function modifies the provided array in place. If you need to preserve the original array, use {slice} instead. */ function splice(bytes32[] memory array, uint256 start, uint256 end) internal pure returns (bytes32[] memory) { // sanitize end = Math.min(end, array.length); start = Math.min(start, end); // move and resize assembly ("memory-safe") { mcopy(add(array, 0x20), add(add(array, 0x20), mul(start, 0x20)), mul(sub(end, start), 0x20)) mstore(array, sub(end, start)) } return array; } /** * @dev Replaces elements in `array` starting at `pos` with all elements from `replacement`. * * Parameters are clamped to valid ranges (e.g. `pos` is clamped to `[0, array.length]`). * If `pos >= array.length`, no replacement occurs and the array is returned unchanged. * * NOTE: This function modifies the provided array in place. */ function replace( bytes32[] memory array, uint256 pos, bytes32[] memory replacement ) internal pure returns (bytes32[] memory) { return replace(array, pos, replacement, 0, replacement.length); } /** * @dev Replaces elements in `array` starting at `pos` with elements from `replacement` starting at `offset`. * Copies at most `length` elements from `replacement` to `array`. * * Parameters are clamped to valid ranges (i.e. `pos` is clamped to `[0, array.length]`, `offset` is * clamped to `[0, replacement.length]`, and `length` is clamped to `min(length, replacement.length - offset, * array.length - pos)`). If `pos >= array.length` or `offset >= replacement.length`, no replacement occurs * and the array is returned unchanged. * * NOTE: This function modifies the provided array in place. */ function replace( bytes32[] memory array, uint256 pos, bytes32[] memory replacement, uint256 offset, uint256 length ) internal pure returns (bytes32[] memory) { // sanitize pos = Math.min(pos, array.length); offset = Math.min(offset, replacement.length); length = Math.min(length, Math.min(replacement.length - offset, array.length - pos)); // replace assembly ("memory-safe") { mcopy( add(add(array, 0x20), mul(pos, 0x20)), add(add(replacement, 0x20), mul(offset, 0x20)), mul(length, 0x20) ) } return array; } /** * @dev Moves the content of `array`, from `start` (included) to the end of `array` to the start of that array, * and shrinks the array length accordingly, effectively overwriting the array with array[start:]. * * NOTE: This function modifies the provided array in place. If you need to preserve the original array, use {slice} instead. */ function splice(uint256[] memory array, uint256 start) internal pure returns (uint256[] memory) { return splice(array, start, array.length); } /** * @dev Moves the content of `array`, from `start` (included) to `end` (excluded) to the start of that array, * and shrinks the array length accordingly, effectively overwriting the array with array[start:end]. The * `end` argument is truncated to the length of the `array`. * * NOTE: This function modifies the provided array in place. If you need to preserve the original array, use {slice} instead. */ function splice(uint256[] memory array, uint256 start, uint256 end) internal pure returns (uint256[] memory) { // sanitize end = Math.min(end, array.length); start = Math.min(start, end); // move and resize assembly ("memory-safe") { mcopy(add(array, 0x20), add(add(array, 0x20), mul(start, 0x20)), mul(sub(end, start), 0x20)) mstore(array, sub(end, start)) } return array; } /** * @dev Replaces elements in `array` starting at `pos` with all elements from `replacement`. * * Parameters are clamped to valid ranges (e.g. `pos` is clamped to `[0, array.length]`). * If `pos >= array.length`, no replacement occurs and the array is returned unchanged. * * NOTE: This function modifies the provided array in place. */ function replace( uint256[] memory array, uint256 pos, uint256[] memory replacement ) internal pure returns (uint256[] memory) { return replace(array, pos, replacement, 0, replacement.length); } /** * @dev Replaces elements in `array` starting at `pos` with elements from `replacement` starting at `offset`. * Copies at most `length` elements from `replacement` to `array`. * * Parameters are clamped to valid ranges (i.e. `pos` is clamped to `[0, array.length]`, `offset` is * clamped to `[0, replacement.length]`, and `length` is clamped to `min(length, replacement.length - offset, * array.length - pos)`). If `pos >= array.length` or `offset >= replacement.length`, no replacement occurs * and the array is returned unchanged. * * NOTE: This function modifies the provided array in place. */ function replace( uint256[] memory array, uint256 pos, uint256[] memory replacement, uint256 offset, uint256 length ) internal pure returns (uint256[] memory) { // sanitize pos = Math.min(pos, array.length); offset = Math.min(offset, replacement.length); length = Math.min(length, Math.min(replacement.length - offset, array.length - pos)); // replace assembly ("memory-safe") { mcopy( add(add(array, 0x20), mul(pos, 0x20)), add(add(replacement, 0x20), mul(offset, 0x20)), mul(length, 0x20) ) } return array; } /** * @dev Access an array in an "unsafe" way. Skips solidity "index-out-of-range" check. * * WARNING: Only use if you are certain `pos` is lower than the array length. */ function unsafeAccess(address[] storage arr, uint256 pos) internal pure returns (StorageSlot.AddressSlot storage) { bytes32 slot; assembly ("memory-safe") { slot := arr.slot } return slot.deriveArray().offset(pos).getAddressSlot(); } /** * @dev Access an array in an "unsafe" way. Skips solidity "index-out-of-range" check. * * WARNING: Only use if you are certain `pos` is lower than the array length. */ function unsafeAccess(bytes32[] storage arr, uint256 pos) internal pure returns (StorageSlot.Bytes32Slot storage) { bytes32 slot; assembly ("memory-safe") { slot := arr.slot } return slot.deriveArray().offset(pos).getBytes32Slot(); } /** * @dev Access an array in an "unsafe" way. Skips solidity "index-out-of-range" check. * * WARNING: Only use if you are certain `pos` is lower than the array length. */ function unsafeAccess(uint256[] storage arr, uint256 pos) internal pure returns (StorageSlot.Uint256Slot storage) { bytes32 slot; assembly ("memory-safe") { slot := arr.slot } return slot.deriveArray().offset(pos).getUint256Slot(); } /** * @dev Access an array in an "unsafe" way. Skips solidity "index-out-of-range" check. * * WARNING: Only use if you are certain `pos` is lower than the array length. */ function unsafeAccess(bytes[] storage arr, uint256 pos) internal pure returns (StorageSlot.BytesSlot storage) { bytes32 slot; assembly ("memory-safe") { slot := arr.slot } return slot.deriveArray().offset(pos).getBytesSlot(); } /** * @dev Access an array in an "unsafe" way. Skips solidity "index-out-of-range" check. * * WARNING: Only use if you are certain `pos` is lower than the array length. */ function unsafeAccess(string[] storage arr, uint256 pos) internal pure returns (StorageSlot.StringSlot storage) { bytes32 slot; assembly ("memory-safe") { slot := arr.slot } return slot.deriveArray().offset(pos).getStringSlot(); } /** * @dev Access an array in an "unsafe" way. Skips solidity "index-out-of-range" check. * * WARNING: Only use if you are certain `pos` is lower than the array length. */ function unsafeMemoryAccess(address[] memory arr, uint256 pos) internal pure returns (address res) { assembly { res := mload(add(add(arr, 0x20), mul(pos, 0x20))) } } /** * @dev Access an array in an "unsafe" way. Skips solidity "index-out-of-range" check. * * WARNING: Only use if you are certain `pos` is lower than the array length. */ function unsafeMemoryAccess(bytes32[] memory arr, uint256 pos) internal pure returns (bytes32 res) { assembly { res := mload(add(add(arr, 0x20), mul(pos, 0x20))) } } /** * @dev Access an array in an "unsafe" way. Skips solidity "index-out-of-range" check. * * WARNING: Only use if you are certain `pos` is lower than the array length. */ function unsafeMemoryAccess(uint256[] memory arr, uint256 pos) internal pure returns (uint256 res) { assembly { res := mload(add(add(arr, 0x20), mul(pos, 0x20))) } } /** * @dev Access an array in an "unsafe" way. Skips solidity "index-out-of-range" check. * * WARNING: Only use if you are certain `pos` is lower than the array length. */ function unsafeMemoryAccess(bytes[] memory arr, uint256 pos) internal pure returns (bytes memory res) { assembly { res := mload(add(add(arr, 0x20), mul(pos, 0x20))) } } /** * @dev Access an array in an "unsafe" way. Skips solidity "index-out-of-range" check. * * WARNING: Only use if you are certain `pos` is lower than the array length. */ function unsafeMemoryAccess(string[] memory arr, uint256 pos) internal pure returns (string memory res) { assembly { res := mload(add(add(arr, 0x20), mul(pos, 0x20))) } } /** * @dev Helper to set the length of a dynamic array. Directly writing to `.length` is forbidden. * * WARNING: this does not clear elements if length is reduced, or initialize elements if length is increased. */ function unsafeSetLength(address[] storage array, uint256 len) internal { assembly ("memory-safe") { sstore(array.slot, len) } } /** * @dev Helper to set the length of a dynamic array. Directly writing to `.length` is forbidden. * * WARNING: this does not clear elements if length is reduced, or initialize elements if length is increased. */ function unsafeSetLength(bytes32[] storage array, uint256 len) internal { assembly ("memory-safe") { sstore(array.slot, len) } } /** * @dev Helper to set the length of a dynamic array. Directly writing to `.length` is forbidden. * * WARNING: this does not clear elements if length is reduced, or initialize elements if length is increased. */ function unsafeSetLength(uint256[] storage array, uint256 len) internal { assembly ("memory-safe") { sstore(array.slot, len) } } /** * @dev Helper to set the length of a dynamic array. Directly writing to `.length` is forbidden. * * WARNING: this does not clear elements if length is reduced, or initialize elements if length is increased. */ function unsafeSetLength(bytes[] storage array, uint256 len) internal { assembly ("memory-safe") { sstore(array.slot, len) } } /** * @dev Helper to set the length of a dynamic array. Directly writing to `.length` is forbidden. * * WARNING: this does not clear elements if length is reduced, or initialize elements if length is increased. */ function unsafeSetLength(string[] storage array, uint256 len) internal { assembly ("memory-safe") { sstore(array.slot, len) } } }