Scala provides the option to define default parameters for functions. This means that the caller would not have to provide those parameters.
The following program shows a simple example of how we can use default parameters.
def name(first:String , last:String = "Einstein") = println(first+" "+last)name("Albert")name("Max", "Planck")
The parameter last
of the name
function in the above code is a default parameter. We have defined its default value as "Einstein"
. Therefore, providing the last
argument in the function call in line 2 was optional.
In line 3, the argument "Planck"
overrides the default argument "Einstein"
.
In the example below, both last
and first
are default parameters. If we specify only one of the parameters, then the first argument will be passed using that parameter, and the second will be taken from the default value, as shown in line 2. We can also omit the first parameter and call the function using the second parameter by naming it, as shown in line 3:
def name(first:String = "Albert" , last:String = "Einstein") = println(first+" "+last)name("Paul")name(last="Markov")
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