method

in_groups

v2.3.8 - Show latest stable - Class: ActiveSupport::CoreExtensions::Array::Grouping

in_groups(number, fill_with = nil)

public

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

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

  %w(1 2 3 4 5 6 7).in_groups(3, '&nbsp;') {|group| p group}
  ["1", "2", "3"]
  ["4", "5", "&nbsp;"]
  ["6", "7", "&nbsp;"]

  %w(1 2 3 4 5 6 7).in_groups(3, false) {|group| p group}
  ["1", "2", "3"]
  ["4", "5"]
  ["6", "7"]

# File activesupport/lib/active_support/core_ext/array/grouping.rb, line 59
        def in_groups(number, fill_with = nil)
          # size / number gives minor group size;
          # size % number gives how many objects need extra accomodation;
          # each group hold either division or division + 1 items.
          division = size / number
          modulo = size % number

          # create a new array avoiding dup
          groups = []
          start = 0

          number.times do |index|
            length = division + (modulo > 0 && modulo > index ? 1 : 0)
            padding = fill_with != false &&
              modulo > 0 && length == division ? 1 : 0
            groups << slice(start, length).concat([fill_with] * padding)
            start += length
          end

          if block_given?
            groups.each{|g| yield(g) }
          else
            groups
          end
        end

in_groups

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