September 2019
Beginner to intermediate
540 pages
13h 3m
English
Content preview from Learn Ethereum
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State variables
State variables are values that are permanently stored in contract storage and are used to maintain the contract's state. As shown in the preceding HelloWorld contract, greeting is the state variable and is defined as a string type with a visibility of X.
The visibility of a state variable can be defined as public, private, or internal, as follows:
- The public variable: The compiler automatically generates the getter method.
- The private variable: The variable is only visible to the smart contract itself, and not even to the child contracts.
- The internal variable: This can be used if you want the state variable to be visible to the smart contract and its child contracts.
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