Script started on Wed Nov  5 11:39:37 2014
bash-3.2$ irb
irb(main):001:0> nums = [1, 2 , 3 4, 5]
=> [1, 2, 3, 5]
irb(main):002:0> nums
=> [1, 2, 3, 5]
irb(main):003:0> nums[1]
=> 2
irb(main):004:0> nums[1,3]
=> [2, 3, 5]
irb(main):005:0> nums[-2]
=> 3
irb(main):006:0> nums
=> [1, 2, 3, 5]
irb(main):007:0> nums[4]=17
=> 17
irb(main):008:0> nums
=> [1, 2, 3, 5, 17]
irb(main):009:0> nums[10] = "ten"
=> "ten"
irb(main):010:0> nums
=> [1, 2, 3, 5, 17, nil, nil, nil, nil, nil, "ten"]
irb(main):011:0> nums.class
=> Array
irb(main):012:0> nums.methods
=> [:inspect, :to_s, :to_a, :to_h, :to_ary, :frozen?, :==, :eql?, :hash, :[], :[]=, :at, :fetch, :first, :last, :concat, :<<, :push, :pop, :shift, :unshift, :insert, :each, :each_index, :reverse_each, :length, :size, :empty?, :find_index, :index, :rindex, :join, :reverse, :reverse!, :rotate, :rotate!, :sort, :sort!, :sort_by!, :collect, :collect!, :map, :map!, :select, :select!, :keep_if, :values_at, :delete, :delete_at, :delete_if, :reject, :reject!, :zip, :transpose, :replace, :clear, :fill, :include?, :<=>, :slice, :slice!, :assoc, :rassoc, :+, :*, :-, :&, :|, :uniq, :uniq!, :compact, :compact!, :flatten, :flatten!, :count, :shuffle!, :shuffle, :sample, :cycle, :permutation, :combination, :repeated_permutation, :repeated_combination, :product, :take, :take_while, :drop, :drop_while, :bsearch, :pack, :entries, :sort_by, :grep, :find, :detect, :find_all, :flat_map, :collect_concat, :inject, :reduce, :partition, :group_by, :all?, :any?, :one?, :none?, :min, :max, :minmax, :min_by, :max_by, :minmax_by, :member?, :each_with_index, :each_entry, :each_slice, :each_cons, :each_with_object, :chunk, :slice_before, :lazy, :nil?, :===, :=~, :!~, :class, :singleton_class, :clone, :dup, :taint, :tainted?, :untaint, :untrust, :untrusted?, :trust, :freeze, :methods, :singleton_methods, :protected_methods, :private_methods, :public_methods, :instance_variables, :instance_variable_get, :instance_variable_set, :instance_variable_defined?, :remove_instance_variable, :instance_of?, :kind_of?, :is_a?, :tap, :send, :public_send, :respond_to?, :extend, :display, :method, :public_method, :singleton_method, :define_singleton_method, :object_id, :to_enum, :enum_for, :equal?, :!, :!=, :instance_eval, :instance_exec, :__send__, :__id__]
irb(main):013:0> nums.length
=> 11
irb(main):014:0> nums.methods.length
=> 169
irb(main):015:0> nums.methods.class
=> Array
irb(main):017:0> nums
=> [1, 2, 3, 5, 17, nil, nil, nil, nil, nil, "ten"]
irb(main):018:0> nums[5,9]=42
=> 42
irb(main):019:0> nums
=> [1, 2, 3, 5, 17, 42]
irb(main):020:0> nums[2]=123
=> 123
irb(main):021:0> nums
=> [1, 2, 123, 5, 17, 42]
irb(main):022:0> nums.sort
=> [1, 2, 5, 17, 42, 123]
irb(main):023:0> nums[2]="ii"
=> "ii"
irb(main):024:0> nums
=> [1, 2, "ii", 5, 17, 42]
irb(main):025:0> nums.sort
ArgumentError: comparison of String with 5 failed
	from (irb):25:in `sort'
	from (irb):25
	from /usr/local/bin/irb:11:in `<main>'
irb(main):026:0> irb(main):026:0> nums
=> [1, 2, "ii", 5, 17, 42]
irb(main):027:0> nums[5]=["an", "array', "of", "strings"]
=> ["an", "array", "of", "strings"]
irb(main):028:0> nums
=> [1, 2, "ii", 5, 17, ["an", "array", "of", "strings"]]
irb(main):029:0> things = Hash.new
=> {}
irb(main):030:0> things
=> {}
irb(main):031:0> things = {"this" => 42, "that" -=> "something else"]}
=> {"this"=>42, "that"=>"something else"}
irb(main):032:0> things
=> {"this"=>42, "that"=>"something else"}
irb(main):033:0> things["this"]
=> 42
irb(main):034:0> things["what"] = "?"
=> "?"
irb(main):035:0> things
=> {"this"=>42, "that"=>"something else", "what"=>"?"}
irb(main):036:0> nums
=> [1, 2, "ii", 5, 17, ["an", "array", "of", "strings"]]
irb(main):037:0> nums = [1,2,3,4,5,6,7]
=> [1, 2, 3, 4, 5, 6, 7]
irb(main):038:0> nums
=> [1, 2, 3, 4, 5, 6, 7]
irb(main):039:0> things.methods
=> [:rehash, :to_hash, :to_h, :to_a, :inspect, :to_s, :==, :[], :hash, :eql?, :fetch, :[]=, :store, :default, :default=, :default_proc, :default_proc=, :key, :index, :size, :length, :empty?, :each_value, :each_key, :each_pair, :each, :keys, :values, :values_at, :shift, :delete, :delete_if, :keep_if, :select, :select!, :reject, :reject!, :clear, :invert, :update, :replace, :merge!, :merge, :assoc, :rassoc, :flatten, :include?, :member?, :has_key?, :has_value?, :key?, :value?, :compare_by_identity, :compare_by_identity?, :entries, :sort, :sort_by, :grep, :count, :find, :detect, :find_index, :find_all, :collect, :map, :flat_map, :collect_concat, :inject, :reduce, :partition, :group_by, :first, :all?, :any?, :one?, :none?, :min, :max, :minmax, :min_by, :max_by, :minmax_by, :each_with_index, :reverse_each, :each_entry, :each_slice, :each_cons, :each_with_object, :zip, :take, :take_while, :drop, :drop_while, :cycle, :chunk, :slice_before, :lazy, :nil?, :===, :=~, :!~, :<=>, :class, :singleton_class, :clone, :dup, :taint, :tainted?, :untaint, :untrust, :untrusted?, :trust, :freeze, :frozen?, :methods, :singleton_methods, :protected_methods, :private_methods, :public_methods, :instance_variables, :instance_variable_get, :instance_variable_set, :instance_variable_defined?, :remove_instance_variable, :instance_of?, :kind_of?, :is_a?, :tap, :send, :public_send, :respond_to?, :extend, :display, :method, :public_method, :singleton_method, :define_singleton_method, :object_id, :to_enum, :enum_for, :equal?, :!, :!=, :instance_eval, :instance_exec, :__send__, :__id__]
irb(main):040:0> things.methods.length
=> 147
irb(main):041:0> nusms
=> [1, 2, 3, 4, 5, 6, 7]
irb(main):042:0> nums.each { puts "boring" }
boring
boring
boring
boring
boring
boring
boring
=> [1, 2, 3, 4, 5, 6, 7]
irb(main):045:0> nums.each { | n | puts n }"exciting " + n }  . t o _ s
exciting 1
exciting 2
exciting 3
exciting 4
exciting 5
exciting 6
exciting 7
=> [1, 2, 3, 4, 5, 6, 7]
irb(main):046:0> total = 0
=> 0
irb(main):047:0> nums.each { |n | total += n }
=> [1, 2, 3, 4, 5, 6, 7]
irb(main):048:0> total
=> 28
irb(main):049:0> things
=> {"this"=>42, "that"=>"something else", "what"=>"?"}
irb(main):051:0> things.each { puts "a thing" } 
a thing
a thing
a thing
=> {"this"=>42, "that"=>"something else", "what"=>"?"}
irb(main):052:0> things.each { | k, v | puts k, v }
this
42
that
something else
what
?
=> {"this"=>42, "that"=>"something else", "what"=>"?"}
irb(main):053:0> 3.times { puts "hello" }
hello
hello
hello
=> 3
irb(main):054:0> 10.times { |n| puts "n = " + n.to_s }
n = 0
n = 1
n = 2
n = 3
n = 4
n = 5
n = 6
n = 7
n = 8
n = 9
=> 10
irb(main):055:0> def search(x, words)
irb(main):056:1>    words.each { | w | if x==w then return end }
irb(main):057:2>    puts "not found"
irb(main):058:2> end
bash-3.2$ exit

Script done on Wed Nov  5 12:19:38 2014