Array.new(5, 1)
[1, 1, 1, 1, 1]
[1] * 5
[1, 1, 1, 1, 1]
array = Array.new(5, 'kawasaki')
array[0].reverse!
array
["ikasawak", "ikasawak", "ikasawak", "ikasawak", "ikasawak"]
Array.new(3) {|i| i.succ }
[1, 2, 3]
Array.new(3) {|i| i + 1 }
[1, 2, 3]
p Array('Bob')
p Array(['Bob'])
Array(nil)
["Bob"] ["Bob"]
[]
Array.wrap('Bob') # need ActiveSupport
NoMethodError: undefined method `wrap' for Array:Class (pry):14:in `<main>' /Users/ariga/.rbenv/versions/2.4.0-preview2/lib/ruby/gems/2.4.0/gems/pry-0.10.4/lib/pry/pry_instance.rb:355:in `eval' /Users/ariga/.rbenv/versions/2.4.0-preview2/lib/ruby/gems/2.4.0/gems/pry-0.10.4/lib/pry/pry_instance.rb:355:in `evaluate_ruby' /Users/ariga/.rbenv/versions/2.4.0-preview2/lib/ruby/gems/2.4.0/gems/pry-0.10.4/lib/pry/pry_instance.rb:323:in `handle_line' /Users/ariga/.rbenv/versions/2.4.0-preview2/lib/ruby/gems/2.4.0/gems/pry-0.10.4/lib/pry/pry_instance.rb:243:in `block (2 levels) in eval' /Users/ariga/.rbenv/versions/2.4.0-preview2/lib/ruby/gems/2.4.0/gems/pry-0.10.4/lib/pry/pry_instance.rb:242:in `catch' /Users/ariga/.rbenv/versions/2.4.0-preview2/lib/ruby/gems/2.4.0/gems/pry-0.10.4/lib/pry/pry_instance.rb:242:in `block in eval' /Users/ariga/.rbenv/versions/2.4.0-preview2/lib/ruby/gems/2.4.0/gems/pry-0.10.4/lib/pry/pry_instance.rb:241:in `catch' /Users/ariga/.rbenv/versions/2.4.0-preview2/lib/ruby/gems/2.4.0/gems/pry-0.10.4/lib/pry/pry_instance.rb:241:in `eval' /Users/ariga/.rbenv/versions/2.4.0-preview2/lib/ruby/gems/2.4.0/gems/iruby-0.2.9/lib/iruby/backend.rb:65:in `eval' /Users/ariga/.rbenv/versions/2.4.0-preview2/lib/ruby/gems/2.4.0/gems/iruby-0.2.9/lib/iruby/backend.rb:12:in `eval' /Users/ariga/.rbenv/versions/2.4.0-preview2/lib/ruby/gems/2.4.0/gems/iruby-0.2.9/lib/iruby/kernel.rb:87:in `execute_request' /Users/ariga/.rbenv/versions/2.4.0-preview2/lib/ruby/gems/2.4.0/gems/iruby-0.2.9/lib/iruby/kernel.rb:47:in `dispatch' /Users/ariga/.rbenv/versions/2.4.0-preview2/lib/ruby/gems/2.4.0/gems/iruby-0.2.9/lib/iruby/kernel.rb:37:in `run' /Users/ariga/.rbenv/versions/2.4.0-preview2/lib/ruby/gems/2.4.0/gems/iruby-0.2.9/lib/iruby/command.rb:70:in `run_kernel' /Users/ariga/.rbenv/versions/2.4.0-preview2/lib/ruby/gems/2.4.0/gems/iruby-0.2.9/lib/iruby/command.rb:34:in `run' /Users/ariga/.rbenv/versions/2.4.0-preview2/lib/ruby/gems/2.4.0/gems/iruby-0.2.9/bin/iruby:5:in `<top (required)>' /Users/ariga/.rbenv/versions/2.4.0-preview2/bin/iruby:22:in `load' /Users/ariga/.rbenv/versions/2.4.0-preview2/bin/iruby:22:in `<main>'
array = [4, 4, 2, 3]
p array.length
p array.empty?
[].empty?
4 false
true
array.include?(4)
true
[1,2,3] + [4,5]
[1, 2, 3, 4, 5]
"abc" + "def"
"abcdef"
[1, 1, 3, 2] - [1, 2]
[3]
[1, 2, 3] & [2, 3, 4]
[2, 3]
[1, 2, 3] | [2, 3, 4]
[1, 2, 3, 4]
[1, 2, 3] * 2
[1, 2, 3, 1, 2, 3]
array = [4, 4, 2, 3]
p array[2]
p array[2, 2]
array[2..4]
2 [2, 3]
[2, 3]
p array.values_at(1)
p array.values_at(1, 3)
[4] [4, 3]
[4, 3]
p array.first
p array.first(2)
p array.last
array.last(2)
4 [4, 4] 3
[2, 3]
array[-2..-1] == array.last(2)
true
p array.sample
array.sample(2)
2
[2, 3]
ary = [[:foo, 4], [:bar, 2], [:buzz, 3]]
ary.assoc(:bar)
[:bar, 2]
ary.assoc(3)
ary2 = [[:foo, 4, 'hoge'], [:bar, 2, 'hogehoge'], [:buzz, 3, 'hogehogehoge']]
ary2.assoc(:buzz)
[:buzz, 3, "hogehogehoge"]
次回、要素の追加と削除から