cast

Creates a transformation-based validation rule chain.

This function allows you to validate a transformed or derived value from the original object. It's useful when you need to validate a computed property, extracted field, or any transformation of the original value. The transformation is applied first, then the chained validation rules are applied to the transformed result.

Usage:

rules<String> {
    notBlank { "must be not blank" }
    cast { it.length } then {
        minimum(3) { "must be at least 3 characters" }
        maximum(20) { "must be at most 20 characters" }
    }
}

Parameters