davidflanagan / javascript6_examples Goto Github PK

Any pointers or speculation on this? Thanks!

Once more time, thanks you for writing "Javascript, The Definitive Guide". I have a question, please answer me, when i upload example 20.05, 20.6, 20.7 to run permanote app, i cannot read and write data to the server by using "note" in manifest file, even i create "note" file in " / " directory. Can you explain how to run it! What do i do more after uploading three files to server!

Thanks and best regard from me!

@davidflanagan in examples/09.12.SingletonSet.js line: 11, shouldn't SingletonSet be passed to extend instead of SingletonSet.prototype ?

Additionally if extend is defined like this:
Function.prototype.extend = function(){}
shouldn't it be used with Set.extend instead of Set.prototype ?

So, from this:

// Now add properties to the prototype.
// These properties override the properties of the same name fro
Set.prototype.extend(SingletonSet.prototype, {...

To this

// Now add properties to the prototype.
// These properties override the properties of the same name fro
Set.extend(SingletonSet.prototype, {...

I don't know if it's an error or it's something I don't get from the chapter. This has been driving me nuts for a couple of days! Thanks.

I love your book so much,it's not only broad also deep,make me think a lot and less confusion.I also preview the 7edition on oreilly,It's also great.I can't wait to own one.But it seems to be take a long time to buy in China.

I have a question to consult you.

var a = {n: 1};
var b = a;
a.x = a = {n: 2};
console.log(a.x);
console.log(b.x);

it is a interview question from internet,and there is a lot of explanations about how to get the result.Most of them just can't convince me.
I have read several times about operator precedence ,order of evaluation part from "the definitive guide", I'm so stuck.

obviously,the key is the third line.
one explanation is "a.x" uses member access(high precedence),so it will evaluate first,it is why "b"and"a" become{n:1;x:undefined},
then the assigment, it has right-to-left associativity,make "a" become a new object{n:2},then assign {n:2} to a.x
Another explanation is order of evaluation,subexpressions will evaluate left-to-right,so "a.x" will evaluate first。

I want to ask some questions

• the reason about why "a.x" evaluate first,the above explanations are all right?the interpreter(compiler) will use two rules to decide?
• what happened when "a.x" evaluating?I found something about property accessor ,it says left-hand operand produces a reference,is this mean a new reference which equals to "a.x" ,ecma-262.

maybe it's just because my shortcoming of compiler and interpreter,I really need someone help me .
Thank you!I'm looking forward to your reply.

Hello, I saw in the introduction to the 75th page of the JavaScript Authoritative Guide(Rhino book): About strict equality operators, if both values are null or both are undefined, they are not equal, but I am in Chrome ( The result in the version is 75.0.3770.100) is like this, because i can't find your mailbox, so ask a question here, sorry, bothering

null===null // true
undefined===undefined // true