By Value vs By Ref

Methods:

• In ruby, arguments inside a method are passed by reference
• In ruby, we have a different situation, the variable that we have inside the method stores a reference to an object.
• Thus, if we will change an object inside the method, then it will be changed also outside the method.

Code

def test_reference(test_hash:)

test_hash[:test] = "was changed inside"

end

outside_hash = { test: "came from the outside" }

puts "before: #{outside_hash}"

test_reference(test_hash: outside_hash)

puts "after: #{outside_hash}"

Output

$ruby main.rb

before: {:test=>"came from the outside"}

after: {:test=>"was changed inside"}