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Declaring Constants
CodeExpectedActual
not_a_constant = 3
not_a_constant = 10
A_CONSTANT = 3
A_CONSTANT = 10
 
warning: already initialized constant A_CONSTANT
 






CONST = 4
module ConstModule
  CONST = 6
end
class ConstHolder
  CONST = 8
  def my_const
    return CONST
  end
end
CONST

4
4





ConstModule::CONST

6
6





ConstHolder::CONST

8
8





ConstHolder.new.my_const

8
8





E = 2.718281828

2.718281828
2.718281828





E = 6                       


warning: already initialized constant E








E

6
6





module Math
 remove_const(:PI)
  PI = 3
end
Math::PI

3
3





RGB_COLORS = [:red, :green, :blue]

[:red, :green, :blue]
[:red, :green, :blue]





RGB_COLORS << :purple

[:red, :green, :blue, :purple]
[:red, :green, :blue, :purple]





RGB_COLORS = [:red, :green, :blue] 


warning: already initialized constant RGB_GOLORS








RGB_COLORS

[:red, :green, :blue]
[:red, :green, :blue]





RGB_COLORS.freeze
RGB_COLORS << :purple


TypeError: can't modify frozen array
...


TypeError: can't modify frozen array
	from (irb):32:in `<<'
	from (irb):32







HOURS_PER_DAY = 24
HOURS_PER_DAY.freeze # This does nothing since Fixnums are already immutable.
HOURS_PER_DAY = 26


warning: already initialized constant HOURS_PER_DAY








HOURS_PER_DAY

26
26