How to get local variable name from object id or memory reference in ruby?

Follow the code :-

class Sample
def bar
  p method(__method__).receiver # only `self` would do the trick.
end
end

n1=Sample.new # => #<Sample:0x13bc648>
n2=Sample.new # => #<Sample:0x13bc630>

n1.bar # => #<Sample:0x13bc648>
n2.bar # => #<Sample:0x13bc630>

But this is my try. I am looking for any method is available in
Ruby,into which say if I pas n1.object_id or #<Sample:0x13bc648>,I will
get back in return the local variable name say here it is - n1 ?

I don’t think that will be possible.

A variable has an identifier ( in your case, n1 ) and a reference to an object ( Sample:0x13bc648 ) so when you say “n1” , it knows which object it references and returns that. As far as I know Ruby doesn’t keep track of reference counts of an object and the object has no way of finding out which variable references itself.

But one inefficient way to achieve what you want would be to iterate through all the local variables and print the names of all local variables that has a particular object ID.

a = b = “hello world”

local_variables.each {|x| puts x if (eval x.to_s).object_id == a.object_id}