description

# int.fromEnvironment constructor Null safety

const int.fromEnvironment(

1. String name,
2. {int defaultValue: 0}

)

Returns the integer value of the given environment declaration `name`.

The result is the same as would be returned by:

    int.tryParse(const String.fromEnvironment(name, defaultValue: ""))
        ?? defaultValue

Example:

    const int.fromEnvironment("defaultPort", defaultValue: 80)

## Implementation

    // The .fromEnvironment() constructors are special in that we do not want
    // users to call them using "new". We prohibit that by giving them bodies
    // that throw, even though const constructors are not allowed to have bodies.
    // Disable those static errors.
    //ignore: const_constructor_with_body
    //ignore: const_factory
    external const factory int.fromEnvironment(String name,
        {int defaultValue = 0});