Appends a new error output variant.

A variant for the current endpoint output will be created using the given Tapir.oneOfVariant. This is needed to capture the logic which allows deciding if a run-time value is applicable to a variant. If the erasure of the E type is different from E, there will be a compile-time failure, as no such run-time check is possible. In this case, use errorOutVariantsFromCurrent and create a variant using one of the other variant factory methods (e.g. Tapir.oneOfVariantValueMatcher).

During encoding/decoding, the new o variant will be checked after the current variant.

More specifically, the current error output is replaced with a Tapir.oneOf output, where:

• the first output variant is the current variant: oneOfVariant(errorOutput)
• the second output variant is the given o

Usage example:

sealed trait Parent
case class Child1(v: String) extends Parent
case class Child2(v: String) extends Parent

val e: PublicEndpoint[Unit, Parent, Unit, Any] = endpoint
  .errorOut(stringBody.mapTo[Child1])
  .errorOutVariant[Parent](oneOfVariant(stringBody.mapTo[Child2]))

Adding error output variants is useful when extending the error outputs in a PartialServerEndpoint, created using EndpointServerLogicOps.serverSecurityLogic.

Replace the error output with a Tapir.oneOf output, using the variants returned by variants. The current output should be included in one of the returned variants.

Allows creating the variant list in a custom order, placing the current variant in an arbitrary position, and using default variants if necessary.

Adding error output variants is useful when extending the error outputs in a PartialServerEndpoint, created using EndpointServerLogicOps.serverSecurityLogic.