Pattern match on value of Either inside a for comprehension?

Question

I have a for comprehension like this:

for {
      (value1: String, value2: String, value3: String) <- getConfigs(args)
      // more stuff using those val         


        

Answer 1

I guess you want your loop to run only if the value is a Right. If it is a Left, it should not run. This can be achieved really easy:

for {
  (value1, value2, value3) <- getConfigs(args).right.toOption
  // more stuff using those values
}

Sidenote: I don't know whats your exact use case, but scala.util.Try is better suited for cases where you either have a result or a failure (an exception).
Just write Try { /*some code that may throw an exception*/ } and you'll either have Success(/*the result*/) or a Failure(/*the caught exception*/).
If your getConfigs method returns a Try instead of Either, then your above could would work without any changes.