Method: Array#in_groups_of

Defined in:
lib/active_support/core_ext/array/grouping.rb

#in_groups_of(number, fill_with = nil) ⇒ Object

Splits or iterates over the array in groups of size number, padding any remaining slots with fill_with unless it is false.

%w(1 2 3 4 5 6 7 8 9 10).in_groups_of(3) {|group| p group}
["1", "2", "3"]
["4", "5", "6"]
["7", "8", "9"]
["10", nil, nil]

%w(1 2 3 4 5).in_groups_of(2, ' ') {|group| p group}
["1", "2"]
["3", "4"]
["5", " "]

%w(1 2 3 4 5).in_groups_of(2, false) {|group| p group}
["1", "2"]
["3", "4"]
["5"]



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# File 'lib/active_support/core_ext/array/grouping.rb', line 22

def in_groups_of(number, fill_with = nil)
  if number.to_i <= 0
    raise ArgumentError,
      "Group size must be a positive integer, was #{number.inspect}"
  end

  if fill_with == false
    collection = self
  else
    # size % number gives how many extra we have;
    # subtracting from number gives how many to add;
    # modulo number ensures we don't add group of just fill.
    padding = (number - size % number) % number
    collection = dup.concat(Array.new(padding, fill_with))
  end

  if block_given?
    collection.each_slice(number) { |slice| yield(slice) }
  else
    collection.each_slice(number).to_a
  end
end