Module: Enumerable

Defined in:
lib/data-table/enum.rb

Overview

Custom Enumerable methods

Instance Method Summary collapse

Instance Method Details

#each_pair_recursive ⇒ Object

Traverse a given nested hash until we reach values that are not hashes.



23
24
25
26
27
28
29
30
31
 
# File 'lib/data-table/enum.rb', line 23

def each_pair_recursive
  each_pair do |k, v|
    if v.is_a?(Hash)
      v.each_pair_recursive { |i, j| yield i, j }
    else
      yield(k, v)
    end
  end
end

#each_pair_with_parents(limit = 0, levels = nil) ⇒ Object

Iterates recusively over a nested collection while keeping track of the ancestor groups.

When passing a block with a third variable the parents will be passed to the block as an array. e.g. [‘parent1’, ‘parent2’, ‘parent3’]

limit can be passed as an optional integer to limit the depth of recursion.

levels is internal use and is used to build the array of ancestors



44
45
46
47
48
49
50
51
52
53
54
55
56
 
# File 'lib/data-table/enum.rb', line 44

def each_pair_with_parents(limit = 0, levels = nil)
  levels ||= []
  each_pair do |k, v|
    levels << k
    if v.is_a? Hash
      v.each_pair_with_parents(limit, levels) { |i, j, next_levels| yield(i, j, next_levels) }
    elsif v.is_a? Array
      levels.pop
      yield(k, v, levels)
    end
  end
  levels.pop
end

#group_by_recursive(groupings) ⇒ Object

Use a set of provided groupings to transform a flat array of hashes into a nested hash. groupings should be passed as an array of hashes. e.g. groupings = [0, 1, 2]



8
9
10
11
12
13
14
15
16
17
18
19
 
# File 'lib/data-table/enum.rb', line 8

def group_by_recursive(groupings)
  groups = group_by do |row|
    row[groupings[0]]
  end
  if groupings.count == 1
    groups
  else
    groups.merge(groups) do |_group, elements|
      elements.group_by_recursive(groupings.drop(1))
    end
  end
end