def f(&b)
  var_inside_method = :foo

  binding_of_this_method = binding
  binding_of_block = b.binding
  binding_inside_block = b.call

  eval "p local_variables", binding_of_this_method
  eval "p local_variables", binding_of_block
  eval "p local_variables", binding_inside_block
end

var_outside_proc = :foo

f { var_inside_proc = :foo; binding }

# Results:
# ["b", "var_inside_method", "binding_of_this_method", "binding_of_block", "binding_inside_block"]
# ["var_outside_proc"]
# ["var_outside_proc", "var_inside_proc"]