What is the “right” way to iterate through an array in Ruby?

PHP, for all its warts, is pretty good on this count. There's no difference between an array and a hash (maybe I'm naive, but this seems obviously right to me), and to iterate through either you just do

foreach (array/hash as $key => $value)

In Ruby there are a bunch of ways to do this sort of thing:

array.length.times do |i|
end

array.each

array.each_index

for i in array

Hashes make more sense, since I just always use

hash.each do |key, value|

Why can't I do this for arrays? If I want to remember just one method, I guess I can use each_index (since it makes both the index and value available), but it's annoying to have to do array[index] instead of just value.


Oh right, I forgot about array.each_with_index. However, this one sucks because it goes |value, key| and hash.each goes |key, value|! Is this not insane?

Answers


This will iterate through all the elements:

array = [1, 2, 3, 4, 5, 6]
array.each { |x| puts x }

Prints:

1
2
3
4
5
6

This will iterate through all the elements giving you the value and the index:

array = ["A", "B", "C"]
array.each_with_index {|val, index| puts "#{val} => #{index}" }

Prints:

A => 0
B => 1
C => 2

I'm not quite sure from your question which one you are looking for.


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