😧Gas Saving Technique 18: Redundant code

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Introduction

When crafting smart contracts, writing efficient and lean code is paramount. Redundant code, or code that doesn't contribute to the functionality, inflates the gas cost without providing any value. In this tutorial, we will discuss how to identify and remove redundant code to optimize gas usage.

Impact & Details

Understanding Redundancy

• Gas Cost Impact: Each line of code in a smart contract consumes gas when deployed and executed. Redundant code increases gas costs unnecessarily, putting an extra burden on users.

• Code Maintainability: Redundant code makes the contract more complex and harder to maintain or audit. Removing unnecessary code simplifies the contract, making it easier to read and understand.

Example: Removing Redundant Code

Below is an example illustrating redundant code and its optimized version:

Before Optimization:

solidityCopy code// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

contract MyContract {
    uint256 public value;

    function setValue(uint256 _value) public {
        require(_value > 0, "Value must be positive");
        value = _value;
        value = value;  // Redundant code
        // ... rest of the function ...
    }
}

After Optimization:

solidityCopy code// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

contract MyContract {
    uint256 public value;

    function setValue(uint256 _value) public {
        require(_value > 0, "Value must be positive");
        value = _value;
        // ... rest of the function ...
    }
}

Recommended Mitigation Steps

1. Review & Identify: Go through the smart contract to identify and list down sections of redundant code. Look for lines that don't alter the contract state or affect the flow of execution.

2. Remove Redundant Code: Once identified, safely remove the redundant code sections without affecting the overall functionality.

3. Testing: After removal, conduct thorough testing to ensure that the contract operates as expected with the redundant code removed.

Conclusion

Removing redundant code is a straightforward practice that yields gas savings and creates cleaner, more maintainable contracts. Every line of code should purposefully contribute to the contract’s functionality. After implementing these changes, meticulously test the contract to ensure it works as intended while being more gas-efficient.