Frequently, the same method X gets called from different objects A, B, C. Is it possible to get a name of the caller object(A, B, C) from inside method X
eg :
class Sample def method # what needs to be done here? end end n1 = Sample.new n2 = Sample.new n1.method #=> expected output is to print n1 n2.method #=> expected output is to print n2 No, this doesn't work. Imaging the following:
n1 = Sample.new n2 = n1 n2.method #=> ambiguous, both n1 and n2 would be valid You could assign a name to your instances instead:
class Sample attr_accessor :name end n1 = Sample.new n1.name = :n1 n2 = Sample.new n2.name = :n2 n1.name #=> :n1 n2.name #=> :n2 
n2.method is not ambiguous syntactically. Instead Ruby's internal structures make it unresolvable (and possible not advisable in any case) to find which pointer was used.
As others said, working with the object_id directly is most probably the much better approach.
Anyway, something along this line might work in your case:
class Sample def method(&b) eval("local_variables.select {|v| eval(v.to_s).object_id == #{object_id}}", b.binding) end end n1 = Sample.new n2 = Sample.new n3 = n2 p n1.method {} #=> [:n1] p n2.method {} #=> [:n2, :n3] p Sample.new.method {} #=> [] It returns all (local) variables in the current scope referencing the callee object. If each of your objects is referenced by exactly one variable, this might be what you are looking for.
Suggested by Neil Slater: you can also use the gem binding_of_caller to simplify transferring the binding:
require 'binding_of_caller' class Sample def method binding.of_caller(1).eval( "local_variables.select {|v| eval(v.to_s).object_id == #{object_id}}" ) end end n1 = Sample.new n2 = Sample.new n3 = n2 p n1.method #=> [:n1] p n2.method #=> [:n2, :n3] p Sample.new.method #=> [] (tested with version 0.7.2 of the gem).
binding_of_caller gem :-)Any object can be identified by its object_id:
class Sample def method puts self.object_id end end n1 = Sample.new n2 = Sample.new puts n1.object_id n1.method puts n2.object_id n2.method --output:-- 2152302060 2152302060 2152302040 2152302040 Variable names...not so much.
Just returning self should work,
Here is an example:
class Sample attr_accessor :name def method puts self puts self.name end end n1 = Sample.new n1.name = "Bangalore" n2 = Sample.new n2.name = "Chennai" n1.method #=> expected output is to print n1 n2.method #=> expected output is to print n2 ------- Output: #<Sample:0x7f492f62c030> # n1 object Bangalore # n1.name #<Sample:0x7f492f62bec8> # n2 object Chennai #n2.name 