defaulted
abstract fun defaulted(name: String, default: OUT, description: String? = null, metadata: Map<String, Any> = emptyMap()): Lens<IN, OUT>
Make a concrete Lens for this spec that falls back to the default value if no value is found in the target.
abstract fun defaulted(name: String, default: LensExtractor<IN, OUT>, description: String? = null, metadata: Map<String, Any> = emptyMap()): Lens<IN, OUT>
Make a concrete Lens for this spec that falls back to another lens if no value is found in the target.