#Ruby 1.6.4 IRB:

irb(main):001:0> C1 = 5
5
irb(main):002:0> def m
irb(main):003:1> C1 = 3
irb(main):004:1> p C1
irb(main):005:1> p ::C1
irb(main):006:1> end
SyntaxError: compile error
(irb):3: dynamic constant assignment
C1 = 3
    ^
        from (irb):6
irb(main):007:0>

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