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Arrays in Ruby

Augusto Kato on August 19, 2023

Today I learned about arrays and their methods in Ruby. Creating Arrays Here are two basic arrays, created by an array literal: num_...
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Birdie •

Worth mention that Array.new also supports block:

Array.new(3) {|index| index * 2 } #=> [0, 2, 4]
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and have to be used if default value is hash/array/object/etc. otherwise they'll share same reference.

# ❌
arr = Array.new(3, {})
arr.first[:a] = 5
arr #=> [{:a=>5}, {:a=>5}, {:a=>5}]

# ✅
arr = Array.new(3) { {} }
arr.first[:a] = 5
arr #=> [{:a=>5}, {}, {}]
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Augusto Kato •

Thanks! I will update the article with this changes!

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Cherry Ramatis •

Nice article!