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Evbn · 2012-08-15 11:10:35

You can't replace a complex concept with a boolean. This isn't JavaScript.

ulucs | karma 1920 | avg karma 2.99 · | 2021-03-06 08:43:37+00:00

Js doesn't really care about types, and doesn't seem to convert a string "true" into a boolean true:

    > temp0.innerHTML = true // no error
    > "true" == true
    false
    > true == "true"
    false

milliams | karma 2525 | avg karma 5.33 · | 2013-10-15 12:56:52+00:00

Does JavaScript not have something like "bool(value)"?

elwell | karma 4299 | avg karma 1.76 · | 2015-04-08 00:50:37+00:00

That's just negation in JS.

pcmaffey | karma 2297 | avg karma 3.21 · | 2018-01-14 18:31:58

`0 === false` is maybe the only thing that I actually hate about javascript. Mutability, I understand and thus can deal with it. Scope, no biggie. But resolving a number to false, when all other numbers resolve to true? Inexplicable.

EDIT: `!0`

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pyfap | karma 34 | avg karma 1.62 · | 2013-02-20 03:36:34+00:00

Saw the title. Immediately thought of something I saw today at work. Not too different from yours. 'if ('True' == 'True')'. I should note that this is javascript generated by a template file.

dbloom | karma 922 | avg karma 8.02 · | 2011-08-05 18:28:03+00:00

That only works if it's surrounded by parenthesies. A bare object literal is not syntactically valid JavaScript.

jQueryIsAwesome | karma 903 | avg karma 1.45 · | 2012-11-15 22:02:55+00:00

Yeah, is one of the things I don't like about JS. The typeof operator should be able to handle those cases. Or a new operator that returns a boolean would be nice.

    if(defined jQuery.unknown.propierties)

leosanchez | karma 342 | avg karma 1.64 · | 2024-02-19 17:00:37

> You cannot override that in Javascript

True. But you they can use a "known Symbol" to implement this feature.

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rhapsodic | karma 2207 | avg karma 2.29 · | 2018-06-30 17:30:27

> Javascript natively is quite difficult to do this and requires a lot of code to handle simple logic.

Statements like this are what boggle my mind. I just don't see what's so damn difficult about native Javascript.

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ajanuary | karma 1304 | avg karma 1.59 · | 2014-08-22 14:28:39

I had to read that paragraph several times to see if they said "But Javascript doesn't do this." Nope, not in there at all.

adjkant | karma 3400 | avg karma 2.84 · | 2018-05-08 15:20:35

Javascript's concatenation and equality rules alone likely will lead to your first premise being incredibly false.

jugg1es | karma 1698 | avg karma 3.83 · | 2017-08-18 14:51:53

Javascript lets you do it if you use the equality (==) instead of the identity (===).. i think.

stephenr | karma 7998 | avg karma 1.42 · | 2019-05-30 21:00:06+00:00

Really? What is hard about “u=rw;g=r;o=“ etc - literally no calculations involved.

This “reinvent things that already work fine but in javascript” is getting old.

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readerrrr | karma 371 | avg karma 1.23 · | 2014-08-28 03:33:52+00:00

Can you do it in js without using conditionals.

tinco | karma 11728 | avg karma 3.67 · | 2021-09-10 03:49:32

You can't do that in idiomatic JavaScript, at least I've never done such a thing in the past 15 years. Maybe you could share an example to show me?

tonyedgecombe | karma 14463 | avg karma 1.72 · | 2019-06-19 18:41:26

I’m not sure a switch statement against a string is a great solution either although to some extent you are restrained by JavaScripts limitations.

pests | karma 3959 | avg karma 1.48 · | 2023-07-24 12:22:51

Why is everyone claiming this is impossible in JavaScript? If you have a POC you should post it so others can learn of the danger.

You've even been quoted elsewhere in this thread about this topic.

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remram | karma 7409 | avg karma 1.74 · | 2019-07-20 00:28:00

It's even more puzzling since those quotes are not required in JavaScript...

IvanK_net | karma 1919 | avg karma 5.0 · | 2018-09-17 09:57:57+00:00

I don't think it is useful to know the behaviour of JS in such cases. In practice, you rarely compare strings with numbers, or objects with booleans.

I wrote tens of thousands of lines of JS (e.g. this library https://github.com/photopea/UPNG.js ), I never used "===" in my life :D

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