How come this.__proto__ being deprecated but Object.getPrototypeOf(this) not implemented?

[espruino-discuss]

Posted at 2016-05-06 by @allObjects

Code using deprecated __proto__ (see screenshot) works:

var Obj = function(val) {


  this.val = (val) ? val : this.__proto__.defaultVal;
};

Obj.prototype.defaultVal = "defaultVal";

Obj.prototype.getVal = function() {
  return this.val;
};

var objDefault = new Obj();

console.log("val = " + objDefault.getVal());

Console output:

 1v85 Copyright 2016 G.Williams
>echo(0);
val = defaultVal
=undefined
> 

Code 'correctly' getting prototype:

...
  this.val = (val) ? val : Object.getPrototypeOf(this).defaultVal; // line 4
...

Console output:

 1v85 Copyright 2016 G.Williams
>echo(0);
Uncaught Error: Function "getPrototypeOf" not found!
 at line 4 col 33
...val = (val) ? val : Object.getPrototypeOf(Obj).defaultVal;...
                              ^
in function "Obj" called from line 1 col 26
var objDefault = new Obj();
                         ^
val =
Uncaught Error: Field or method "getVal" does not already exist, and can't create it on undefined
 at line 1 col 34
console.log("val = " + objDefault.getVal());
                                 ^
=undefined
>

---

Attachments:

• Screen Shot 2016-05-06 at 8.38.46 AM.png

[gfwilliams]

Posted at 2016-05-06 by @gfwilliams

This'll be the JSHint (the lint plugin for the Web IDE) picking up on something. __proto__ isn't deprecated in Espruino, although I guess Object.getPrototypeOf should be added at some point.

[espruino-discuss]

Posted at 2016-05-06 by DrAzzy

So it's just the linter bitching about __proto__ - Is it actually officially deprecated anywhere or anything, or do they just not like it because it doesn't feel JS-y enough?

Object.getPrototypeOf is not listed in the reference, so it's no surprise that it's not implemented (the reference list is exhaustive, right? I think it's autogenerated so all methodscd show up, even if there's no info on them).

Edit: beaten....

[espruino-discuss]

Posted at 2016-05-06 by @allObjects

Thanks. I like the light-weight obj.__proto__ property accessor but understand why it got deprecated and replaced with Object.getPrototypeOf(obj) method.

I see the challenge of keeping up with JS ECMA... and it will get more intense... ES6... 7. But it is for sure fun and you - including every one else - will not get bored...

[espruino-discuss]

Posted at 2016-05-06 by @allObjects

I'm now thinking IDE could use a (user configurable) profile about what is ultimately fed to the linter... (no pressure on anyone...)

[gfwilliams]

Posted at 2016-05-09 by @gfwilliams

I liked __proto__ too, but it does feel a bit hacky :) I'll add an issue for sticking getPrototypeOf in.

the reference list is exhaustive, right?

Yep, it's whatever is in the current release of Espruino, so at the moment 1v85. There may be some other stuff in the latest Git build.

about what is ultimately feed to the linter...

@allObjects - https://github.com/espruino/EspruinoWebIDE/blob/gh-pages/js/core/editorJavaScript.js#L29 :)

I'm not sure it needs to be configurable, but disabling just that warning should be easy.