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kalasoo/array_of_array.rb

Last active August 29, 2015 14:00
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Array of Array appending
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array_of_array.rb
# Just found an interesting stuff
x = [[]] * 4 # [[], [], [], []]
x[0] << 1 # or x[0] .push 1
# => [[1], [1], [1], [1]]
# Reason
x = [[]] * 4
puts x.each {|a| puts a.object_id }
x = Array.new(4) { [] }
puts x.each {|a| puts a.object_id }
# >> 70261926896280
# >> 70261926896280
# >> 70261926896280
# >> 70261926896280
# >> 70261926887120
# >> 70261926887100
# >> 70261926887060
# >> 70261926887040
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