class ArgumentError - Ruby 2.2.4 Core API Reference API Reference
From Ruby 2.2 Core API
class ArgumentError
Raised when the arguments are wrong and there isn't a more specific Exception class.
Ex: passing the wrong number of arguments
[1, 2, 3].first(4, 5)
raises the exception:
ArgumentError: wrong number of arguments (2 for 1)
Ex: passing an argument that is not acceptable:
[1, 2, 3].first(-4)
raises the exception:
ArgumentError: negative array size