OZ SafeMath.md

175 - OZ SafeMath

OpenZeppelin SafeMath: provides mathematical functions that protect your contract from overflows and underflows. Include the contract with using SafeMath for uint256; and then call the functions:

1. myNumber.add(otherNumber): Returns the addition of two unsigned integers, reverting on overflow. Counterpart to Solidity's + operator.

2. myNumber.sub(otherNumber): Returns the subtraction of two unsigned integers, reverting on overflow (when the result is negative). Counterpart to Solidity's - operator.

3. myNumber.div(otherNumber): Returns the division of two unsigned integers, reverting on overflow. The result is rounded towards zero. Counterpart to Solidity's / operator.

4. myNumber.mul(otherNumber): Returns the multiplication of two unsigned integers, reverting on overflow. Counterpart to Solidity's * operator.

5. myNumber.mod(otherNumber): Returns the modulus of two unsigned integers, reverting when dividing by zero. Counterpart to Solidity's % operator.

The corresponding try* functions return results with an overflow flag instead of reverting.

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• Math Functions
• Safe -> Overflow/Underflow
• add & sub & mul & div & mod
• using SafeMath for uint256
• try* -> Flag vs Revert
• Required: solc < 0.8.0

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References

• Youtube Reference

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