If you have an array of ranges, such as [1..4, 7..11, 14..18, 21..25, 28..28]
, what options do I have for iterating through the elements?
I could do
ranges.each do |range|
range.each do |date|
puts "Do work on February #{date}"
end
end
which is a开发者_运维技巧 bit verbose, or I could do
dates = ranges.map(&:to_a).flatten
dates.each do |date|
puts "Do work on February #{date}"
end
which could use a lot of memory if the ranges are large.
Are there any alternatives?
Well, I don't think your first answer is too verbose, but if that pattern is getting used often enough, it might make the case for something like this -
module Enumerable
def each_node
each do |x|
(x.respond_to?(:each_node)) ? x.each_node{ |y| yield(y) } : yield(x)
end
end
end
[[[(1..5)], (1..2)],1].each_node { |x| print x } #=> 12345121
ranges = [1..4, 7..11, 14..18, 21..25, 28..28]
ranges.each_node{ |date| puts "Do work on February #{date}" } #=>as expected
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