18 lines
622 B
Solidity
18 lines
622 B
Solidity
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// SPDX-License-Identifier: GPL-2.0-or-later
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pragma solidity >=0.5.0;
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/// @title Math library for liquidity
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library LiquidityMath {
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/// @notice Add a signed liquidity delta to liquidity and revert if it overflows or underflows
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/// @param x The liquidity before change
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/// @param y The delta by which liquidity should be changed
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/// @return z The liquidity delta
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function addDelta(uint128 x, int128 y) internal pure returns (uint128 z) {
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if (y < 0) {
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require((z = x - uint128(-y)) < x, 'LS');
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} else {
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require((z = x + uint128(y)) >= x, 'LA');
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}
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}
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}
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