no-immutable-before-declaration

The {"extends": "solhint:recommended"} property in a configuration file enables this rule.

Description

Immutable variables should not be used in state variable initializers before they are declared.

Options

This rule accepts a string option for rule severity. Must be one of "error", "warn", "off". Defaults to warn.

Example Config

{
  "rules": {
    "no-immutable-before-declaration": "warn"
  }
}

Examples

👍 Examples of correct code for this rule

Immutable declared before being used in another initializer

            contract Immutables {
                uint256 internal immutable immB = 25;
                uint256 public immA = immB + 100; // OK, immB is already declared
            }
          

Constants can be referenced before declaration

            contract Immutables {
                uint256 public constA = constB + 100; // OK, constants are compile-time
                uint256 internal constant constB = 50;
            }
          

👎 Examples of incorrect code for this rule

Immutable used before declaration in state variable initializer

            contract Immutables {
                uint256 public immA = immB + 100; // BAD: immB declared later
                uint256 internal immutable immB = 25;
            }
          

Version

This rule was introduced in Solhint 6.0.2

Resources

• Rule source
• Document source
• Test cases