let isProto = function(obj1, obj2){
let target1 = obj1.__proto__,
target2 = obj2.prototype;
while(true){
if(target1 === target2){
return true;
}else if(target1 === null){
return false;
}else{
target1 = target1.__proto__;
}
}
}
let isProto = function(obj1, obj2){
let target1 = obj1.__proto__,
target2 = obj2.prototype;
while(true){
if(target1 === target2){
return true;
}else if(target1 === null){
return false;
}else{
target1 = target1.__proto__;
}
}
}