questions about es5 inheriting subconstructor prototypes
Line 5 of the code
I can understand that the prototype of the fourth line of child constructor is Sub.protorype = new Super ()
from the parent constructor new, so here Sub.protorype.constructor = Super is
for true. What is the reason for redirecting the constructor of the prototype of the child constructor to itself?
I find that Sub.protorype.constructor = Sub can also inherit
can be inherited, but the instance of Sub made a mistake when getting constructor. It is obviously wrong to become Super. This is a side effect. This side effect should be corrected.
constructor just tells you which constructor the instance is initialized with, and does not affect the prototype chain
Sub.protorype.constructor = Sub;whether the above sentence is written or not, it does not affect the prototype chain, and the following code is always true
. Sub.prototype.__proto__.__proto__ === Object.prototype //
sub1 instanceof Super
sub1 instanceof Sub //1Subin short, the prototype chain depends on _ _ proto__, and constructor is just a pointer attribute for detection
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