It is not possible to leave out some implicit parameters. So, in your example
def foo(implicit a: Int, b: String): Unit = ???
It is not possible to only specify a
. However, you can specify the default value of the implicit parameter, for example
def foo(implicit a: Int, b: String = "---"): Unit = ???
Where if b
is not implicitly available, "---"
will be used.
Remember that the implicit
keyword marks the parameter list as implicit, not that one parameter as implicit.