The implicit parameter, as opposed to the regular parameter, can be passed silently to a method without going through the regular parameter list. The implicit keyword indicates these parameters and any parameters following the implicit keyword are implicit. Essentially, when we don't pass anything to methods or functions, the compiler will look for an implicit value and use that as a parameter. Whenever implicit keywords appear in a function's parameter scope, this marks all parameters as implicit. Each method can simply have a single implicit keyword.
Syntax:
def func1(implicit a : Int) // a is implicit
def func2(implicit a : Int, b : Int) // a and b both are implicit
def func3 (a : Int)(implicit b : Int) // only b is implicit
Example:
object InterviewBit
{
def main(args: Array[String])
{
val value = 20
implicit val addition = 5
def add(implicit to: Int) = value + to
val result = add
println(result)
}
}
Output:
25
