Apply side effect only if OptArg is empty.
Apply side effect only if OptArg is empty. It's a bit like foreach for OptArg.Empty
- code to be executed if optArg is empty
the same optArg
captionOptArg.forEmpty(logger.warn("caption is empty")).foreach(setCaption)
OptArg is like Opt except it's intended to be used to type-safely express optional method/constructor parameters while at the same time avoiding having to explicitly wrap arguments when passing them (thanks to the implicit conversion from
AtoOptArg[A]). For example:Note that like Opt, OptArg assumes its underlying value to be non-null and
nullis translated intoOptArg.Empty.It is strongly recommended that OptArg type is used ONLY in signatures where implicit conversion
A => OptArg[A]is intended to work. You should not use OptArg as a general-purpose "optional value" type - other types like Opt, NOpt and scala.Option serve that purpose. For this reason OptArg deliberately does not have any "transforming" methods likemap,flatMap,orElse, etc. Instead it's recommended that OptArg is converted to Opt, NOpt or scala.Option as soon as possible (usingtoOpt,toNOptandtoOptionmethods).