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javascript - Prototype object Date inheritance not working

Considering this works.

Prototype:

function A(color){
 this.color = color
}

A.prototype.test = function(){
 return this.color
}

Inheritance:

function B(){
 A.call(this)
}

B.prototype = Object.create(A.prototype)
B.prototype.constructor = B

B.prototype.test2 = function(){
 return 'whatever...'
}

Instance:

const inst = new B(black)
console.log(inst.test()) //black
console.log(inst.test2()) //whatever...

Because this doesn't work.

Date object inheritance:

function A(){
 Date.call(this)
}

A.prototype = Object.create(Date.prototype)
A.prototype.constructor = A

A.prototype.test = function(){
 return 'whatever...'
}

Instance:

console.log(new A().getDay()) //Uncaught TypeError: this is not a Date object.
console.log(new A().test()) //whatever...

I tried inheriting with class syntax and it works perfect but not what I want

Date object inheritance with class:

class A extends Date {
 constructor(){
  super()
 }
 test(){
  return 'whatever...'
 }
}

Instance:

console.log(new A().getDay()) //3
console.log(new A().test()) //whatever...

It works perfect, but I don't want to use the class syntax.

question from:https://stackoverflow.com/questions/65913269/prototype-object-date-inheritance-not-working

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