javascript - JS object, need explanation of what's happening and why -

javascript - JS object, need explanation of what's happening and why -

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console.log() async or sync? 2 answers

this code pet:

function pet() { this.vitals = new vitals(); } function vitals() { this.hunger = 5; this.thirst = 0; this.emotions = { happy: true, sad: true } }

below calling , forth:

$(document).ready(function () { var pet = new pet(); console.log(pet); pet.vitals.emotions.happy = false; console.log(pet); });

this console:

question: why happy false in both readouts, , not sec one?

probably because console.log can update info printed if underlying object reference updated afterwards. seek create reference called pet2 see trick.

by way, should check this , this.

javascript json object