SafeValues

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Value generates Struct classes with safer constructors. It is designed to provide a superset of the interface of the Values gem, with better performance, by subclassing actual native Structs.

Value constructors require all mandatory arguments to be provided, and supply default values for all optional arguments. Additionally, the resulting instance is frozen. To obtain a mutable Value, use dup.

Value types are created similarly to Structs, with the addition that optional arguments are may be specified as keyword arguments:

ValueType = Value.new(:a, :b, c: default_value)

The default values to optional arguments are saved at class creation time and supplied as default constructor arguments to instances. Default values are aliased, so providing mutable defaults is discouraged.

Two instance constructors are provided, with positional and keyword arguments.

Value types may be constructed with positional arguments using new. Arguments are provided in the same order as specified at class initialization time, with mandatory arguments before optional ones. For example:

ValueType.new(1, 2) or ValueType.new(1, 2, 3)

Value types may be constructed with keyword arguments using with. For example:

ValueType.with(a: 1, b: 2) or ValueType.with(a: 1, b: 2, c: 3)