Ruby changes constants!

class Something
 CONSTANT_VALUES = ["Hooray - I have substance!", "Something Else"]

 def self.do_something
   puts "Constant value = #{Something::CONSTANT_VALUES.inspect}"
   puts "Method Value = #{self.apply_something(Something::CONSTANT_VALUES)}"
 end
 
 def self.apply_something(values)
   value_changed = [*values]
   value_changed.slice!(0,30).each do |value|
      #Do any processing
   end
   values
 end

end   

--------------

>> Something.do_something
Constant value = ["Hooray - I have substance!", "Something Else"]
Method Value = 
=> nil
>> Something.do_something
Constant value = []
Method Value = 
=> nil
>> Something.do_something
Constant value = []
Method Value = 
=> nil


--------------

Ruby changes constants :( - in this instance it is the .slice! doing the dirty deed, to correct this we still need a 'dup' even on passed constants:


class Something
 CONSTANT_VALUES = ["Hooray - I have substance!", "Something Else"]

 def self.do_something
   puts "Constant value = #{Something::CONSTANT_VALUES.inspect}"
   puts "Method Value = #{self.apply_something(Something::CONSTANT_VALUES)}"
 end
 
 def self.apply_something(values)
   value_changed = [*values.dup]
   value_changed.slice!(0,30).each do |value|
      #Do any processing
   end
   values
 end

end  


---------------

>> Something.do_something
Constant value = ["Hooray - I have substance!", "Something Else"]
Method Value = Hooray - I have substance!Something Else
=> nil
>> Something.do_something
Constant value = ["Hooray - I have substance!", "Something Else"]
Method Value = Hooray - I have substance!Something Else
=> nil