E171: Missing Argument
This error occurs when a method is called without providing all required arguments.
When calling a method, you must provide values for all parameters that don't have default values. This error identifies which parameter is missing from the call.
Example
def greet(name: String, greeting: String) = s"$greeting, $name!"
def test = greet("World")
Error
-- [E171] Type Error: example.scala:3:16 ---------------------------------------
3 |def test = greet("World")
| ^^^^^^^^^^^^^^
|missing argument for parameter greeting of method greet: (name: String, greeting: String): String
Solution
def greet(name: String, greeting: String) = s"$greeting, $name!"
// Provide all required arguments
def test = greet("World", "Hello")
// Or use default parameter values
def greet(name: String, greeting: String = "Hello") = s"$greeting, $name!"
def test = greet("World")
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