diff options
Diffstat (limited to 'activesupport/lib/active_support')
-rw-r--r-- | activesupport/lib/active_support/core_ext/array/grouping.rb | 47 |
1 files changed, 45 insertions, 2 deletions
diff --git a/activesupport/lib/active_support/core_ext/array/grouping.rb b/activesupport/lib/active_support/core_ext/array/grouping.rb index 767acc4e07..df37afb053 100644 --- a/activesupport/lib/active_support/core_ext/array/grouping.rb +++ b/activesupport/lib/active_support/core_ext/array/grouping.rb @@ -4,8 +4,8 @@ module ActiveSupport #:nodoc: module CoreExtensions #:nodoc: module Array #:nodoc: module Grouping - # Iterates over the array in groups of size +number+, padding any remaining - # slots with +fill_with+ unless it is +false+. + # 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).in_groups_of(3) {|g| p g} # ["1", "2", "3"] @@ -39,6 +39,49 @@ module ActiveSupport #:nodoc: end end + # 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) {|g| p g} + # ["1", "2", "3", "4"] + # ["5", "6", "7", nil] + # ["8", "9", "10", nil] + # + # %w(1 2 3 4 5 6 7).in_groups(3, ' ') {|g| p g} + # ["1", "2", "3"] + # ["4", "5", " "] + # ["6", "7", " "] + # + # %w(1 2 3 4 5 6 7).in_groups(3, false) {|g| p g} + # ["1", "2", "3"] + # ["4", "5"] + # ["6", "7"] + 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 + # Divides the array into one or more subarrays based on a delimiting +value+ # or the result of an optional block. # |