When passing objects as parameters, are they passed by reference?

Question

Is there any performance implications if I do either of these:

def do_something(user, article)
...
end

versus

def do_someth         


        

Answer 1

No, Ruby never passes by reference. Ruby is pass-by-value. Always. No exceptions.

def is_Ruby_pass_by_value_or_reference?(parameter)
  parameter = 'Ruby is pass-by-reference.'
end

var = 'Ruby is pass-by-value. Always. No exceptions.'

is_Ruby_pass_by_value_or_reference?(var)

puts var
# Ruby is pass-by-value. Always. No exceptions.

If Ruby were pass-by-reference, this would print Ruby is pass-by-reference.