Converting ruby array to array of consecutive pairs

Question

What is the easiest way to convert a ruby array to an array of consecutive pairs of its elements?

I mean:

x = [:a, :b, :c, :d]

Expected result:

y #=> [[:a, :b], [:c, :d]]

Stefan · Accepted Answer · 2017-07-03 06:56:09Z

90

y = x.each_slice(2).to_a
#=> [[:a, :b], [:c, :d]]

[0, 1, 2, 3, 4, 5].each_slice(2).to_a
#=> [[0, 1], [2, 3], [4, 5]]

Stefan

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answered Aug 13, 2010 at 14:31

deinst

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Comments

Daniel O'Hara · Accepted Answer · 2010-08-13 14:30:50Z

4

Hash[*[:a, :b, :c, :d]].to_a

answered Aug 13, 2010 at 14:30

Daniel O'Hara

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Clever, but it does not preserve the order.

It does (at least in Ruby 1.9.2dev).

It also fails if there happens to be a duplicate key. Hash[*[:a,:b,:c,:d,:a,:e]]

Also fails if length of array is not divisible by 2. - Hash[*[1,2,3]].to_a fails [1,2,3].each_slice(2).to_a doesn't