steps
- Open https://www.scala-sbt.org/1.x/docs/Parsing-Input.html#Combining+parsers
- Copy-paste line
val color: Parser[String] = "blue" | "green"
in sbt console or in build.sbt
problem
error: value | is not a member of String
expectation
A parser that succeeds if the input is "blue" or "green" as wrote in the documentation.
notes
sbt 1.2.8, 1.6.2
scala 2.12.10