trait Optional[A] extends Serializable
Type class that represents data types that have an "empty" value.
The purpose of this type class is to allow automatic derivation of Decoder for decoded types that might not have
a value - Option
, List
...
In theory, there should rarely be a need to interact directly with this type class, and one is usually better served
by obtaining the Decoder instance for Option
and mapping on it.
- Source
- Optional.scala
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