🕶️Gas Saving Technique 39: Avoiding Duplicated Code for Gas Savings

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Introduction: Duplicated code, also known as code redundancy, not only affects the readability and maintainability of smart contracts but also has a direct impact on deployment and execution costs. Each repeated line of code contributes to the overall size of a contract, leading to increased gas costs. This tutorial highlights the importance of avoiding duplicated code for gas efficiency.

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Concept:

1. Duplicated Code: Refers to identical or very similar blocks of code that appear in multiple locations in a contract.

2. Gas Efficiency: The measure of how effectively a contract utilizes the gas required for deployment and transaction execution. Duplicated code negatively impacts gas efficiency by increasing the overall bytecode size.

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Reasons to Avoid Duplicated Code:

1. Increased Deployment Costs: The larger the contract's bytecode, the more gas required to deploy it on the Ethereum network.

2. Higher Transaction Costs: Repeated operations can lead to higher execution costs for transactions.

3. Maintenance Challenges: Duplicated code can introduce bugs and make it harder to update or modify the contract in the future.

4. Readability: Redundant code makes it harder for developers to understand the contract's logic, potentially leading to errors or overlooked vulnerabilities.

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Techniques to Reduce Duplicated Code:

1. Modularization:

   • Break your contract into smaller, reusable components or functions.

   • For example, if multiple functions use the same logic for checking user permissions, move that logic into a separate internal function.

2. Use Libraries:

   • Externalize common logic into libraries. This allows you to reuse code across different contracts.

   • Example: SafeMath library in Solidity for arithmetic operations.

3. Inheritance and Interfaces:

   • Use inheritance to create base contracts with shared logic that can be inherited by other contracts.

   • Define interfaces for contracts that can implement common functionality.

4. State Variable Initialization:

   • If multiple functions initialize the same state variables with default values, consider setting these defaults during contract deployment to avoid redundancy.

Conclusion: Avoiding duplicated code is essential for writing gas-efficient, readable, and maintainable smart contracts. Regularly reviewing and refactoring contracts to minimize redundancy can save developers both gas and potential headaches in the long run.