Introduction

Unused Parameter refers to methods with parameters that are unused in scope of the method.

Having unused parameters in a method is code smell because leaving dead code in a method can never improve the method and it makes the code confusing to read.

Example

Given:

class Klass
  def unused_parameters(x,y,z)
    puts x,y # but not z
  end
end

reek would emit the following warning:

[2]:Klass#unused_parameters has unused parameter 'z' (UnusedParameters)

Configuration

Unused Parameter offers the Basic Smell Options.