javascript-Object.md

Object.defineProperty()

• configurable
• enumerable
• writable
• value
• get & set function

References

• https://stackoverflow.com/a/18557503/3000082

prototype vs __proto__

All objects have an internal property called [[Prototype]]. The value of this property is either null or an object and is used for implementing inheritance.

[[Prototype]]

• An object specifies its prototype via the internal property

proto

• This brings direct access to [[Prototype]] to the language(by speakingjs.com).

• __proto__ is the actual object that is used in the lookup chain to resolve methods, etc. prototype is the object that is used to build __proto__ when you create an object with new:

prototype

• prototype is the object that is used to build __proto__ when you create an object with new.
• prototype is not available on the instances themselves (or other objects), but only on the constructor functions.
• prototype is only available on functions since they are copied from Function and Object, but in anything else it is not. However, __proto__ is available everywhere.

( new Foo ).__proto__ === Foo.prototype;
( new Foo ).prototype === undefined;

Reference:

• https://hackernoon.com/understand-nodejs-javascript-object-inheritance-proto-prototype-class-9bd951700b29
• https://stackoverflow.com/questions/9959727/proto-vs-prototype-in-javascript
• https://stackoverflow.com/questions/9451881/prototype-vs-prototype-what-is-the-difference-mycons-proto-myco/46463288#46463288

Object.freeze vs Object.seal vs Object.preventextensions

Reference

• https://medium.com/@nlfernando11/object-freeze-vs-object-seal-vs-object-preventextensions-251ee99d0c47

Object Inheritence

Object Clone

Deep copy

• https://stackoverflow.com/a/728694/3000082

Convert JSON and back

 JSON.parse(JSON.stringify(nestedObject));

Swallow copy

1. Spreed Operator
2. Object.assign({}, Obj1)

Reference

• https://medium.com/better-programming/3-ways-to-clone-objects-in-javascript-f752d148054d
• https://stackoverflow.com/questions/122102/what-is-the-most-efficient-way-to-deep-clone-an-object-in-javascript
• https://stackoverflow.com/questions/32925460/object-spread-vs-object-assign

Object.getOwnPropertyDescriptor(s)()

Object.is(obj1, obj2) - Compare two Object

native object vs Host Object

https://stackoverflow.com/a/7614380

class (static) method vs class prototype method

• https://stackoverflow.com/questions/1635116/javascript-class-method-vs-class-prototype-method
• https://stackoverflow.com/questions/11249037/javascript-this-in-static-methods

My other useful GIST

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• Sorting Objects - https://gist.github.com/thamsrang/f3178b17002d74d6f4b3766af50ca358
• Event Handler - https://gist.github.com/thamsrang/ba6a14d06cce3bb704567d8d918a12fb
• Javascript key terms - https://gist.github.com/thamsrang/8aa48e568fb5c5c5964baf205f2b6e0d
• type_coercion - https://gist.github.com/thamsrang/ceda5f22af8923acb9a2e7d831b6a5be