Use nodejs to implement PHP's print_r function code_javascript skills

function ergodic(obj,indentation){
  var indent = "  " indentation;
  if(obj.constructor == Array || obj.constructor == Object){

    for(var p in obj){
      if(obj[p].constructor == Array|| obj[p].constructor == Object){
        console.log(indent "[" p "] => " typeof(obj) "");
        console.log(indent "{");
        ergodic(obj[p], indent);
        console.log(indent "}");
      } else if (obj[p].constructor == String) {
        console.log(indent "[" p "] => '" obj[p] "'");
      } else {
        console.log(indent "[" p "] => " obj[p] "");
      }
    }
  }
}

function print_r(obj) {
  console.log("{")
  ergodic(obj, "");
  console.log("}")
}

var stu = {'name':'Alan','grade':{'Chinese':120,'math':130,'competition':{'NOI':'First prize'}}};

print_r(stu);