lib/open_classes/array.rb in tbpgr_utils-0.0.19 vs lib/open_classes/array.rb in tbpgr_utils-0.0.20

@@ -131,20 +131,40 @@
     memo
   end
 
   # Arrays bulk concat.
   #
+  # together_concat has alias :tconcat
+  #
   #   alpha = %w{one two three}
   #   numbers = %w{1 2 3}
   #   [alpha, numbers].together do |first, second|
   #     print "#{first}:#{second}\n"  # => output one:1, two:2, three:3
   #   end
   def together_concat(other)
     if_not_contain_array_rails_type_error
     each { |list|list.concat other }
   end
 
+  # Arrays bulk at.
+  #
+  # together_at has alias :tat
+  #
+  # same elements size case
+  #   alpha = %w{one two three}
+  #   numbers = %w{1 2 3}
+  #   [alpha, numbers].together_at 2 # => output ['three', 3]
+  #
+  # different elements size case
+  #   alpha = %w{one two three}
+  #   numbers = %w{1 2 nil}
+  #   [alpha, numbers].together_at 2 # => output ['three', nil]
+  def together_at(index)
+    if_not_contain_array_rails_type_error
+    reduce([]) { |ats, list|ats << list.at(index) }
+  end
+
   private
 
   def if_not_contain_array_rails_type_error
     each { |f|fail TypeError, "you have to use [Array1, Array2, ...] | #{f.class} is invalid" unless f.class == Array }
   end
@@ -189,9 +209,10 @@
   def together_return_multi?(list)
     (list.class == Array && list.size == size).to_bool
   end
 
   alias_method :tconcat, :together_concat
+  alias_method :tat, :together_at
   alias_methods [:together_collect, :tmap, :tcollect], :together_map
   alias_methods [:together_find_all, :tselect, :tfindall], :together_select
   alias_methods [:together_inject, :treduce, :tinject], :together_reduce
 end