Clear DefinitionsConstructor
1 min read
Pronunciation
[kuhn-struhk-ter]
Analogy
Imagine building a new house (deploying a smart contract). The 'constructor' is like the final setup and inspection process performed by the builder right when the house is completed and handed over. This process might involve setting the initial lock combinations (initializing state variables), recording the owner's name, and ensuring everything is in its correct starting place. This setup happens only once for that specific house.
Definition
A special function in a smart contract that is executed only once, at the time the contract is deployed to the blockchain. It is primarily used to initialize the contract's state variables and set up its initial conditions.
Key Points Intro
The constructor is a special initialization function executed upon smart contract deployment.
Key Points
A special function automatically called only when the contract is first deployed.
Used to set initial values for state variables, define ownership, or configure parameters.
In Solidity, the constructor is declared using the `constructor` keyword and has the same name as the contract (in older versions) or just `constructor` (in newer versions).
Can accept arguments, which are provided at the time of deployment.
If no constructor is defined, a default empty constructor is used.
Example
When deploying an ERC-20 token contract, the constructor might take parameters for the token's name (e.g., "MyToken"), symbol (e.g., "MYT"), and initial supply. These values are then set in the contract's state during deployment.
Technical Deep Dive
The bytecode for the constructor is part of the contract creation code. When a contract deployment transaction is processed, the constructor code is executed. Any arguments passed during deployment are made available to the constructor. After the constructor finishes execution, its bytecode is discarded, and the remaining runtime bytecode of the contract (containing its regular functions) is stored on the blockchain at the new contract's address. State variables initialized in the constructor become part of the contract's persistent storage.
Constructor - Related Articles
No related articles for this term.