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JavaScript Is Weird

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Re: JavaScript Is Weird

#361

Post by Tainnor »

JoshuaDavid wrote: post #312
otabdeveloper4 wrote: post #309

Earlier quoted context omitted.

Having the full number stack supported (natural numbers - integers - rationals - reals) would be, indeed, awesome. Sadly, most people don't understand the distinctions, so this will never happen. (Even in reply to your post people keep talking about "decimals", as if the number base is at all relevant here.)

"Decimal" usually refers to a data type which is "integer, shifted by a known number of decimal places". So, for example, if you had an amount of money $123.45, you could represent that as a 32-bit floating point number with (sign=0 (positive), exponent=133, mantissa=7792230) which is 123.4499969482421875, but you would probably be better off representing it with a decimal type which represents the number as (integer…

Non-decimal currencies have existed in the past and there are still some remnants: https://en.wikipedia.org/wiki/Non-decimal_currency

Re: JavaScript Is Weird

#362

Post by Tainnor »

otabdeveloper4 wrote: post #309
Tainnor wrote: post #257

Earlier quoted context omitted.

I've been thinking for a while that modern languages shouldn't default to floating point computations. They're exactly the right thing if you do data stuff or scientific computing, but given how much of the internet relies on things like e-commerce and how often floating point is still misused for dealing with money, coupled with the fact that even many senior developers aren't fully aware of the subtleties of floati…

Having the full number stack supported (natural numbers - integers - rationals - reals) would be, indeed, awesome. Sadly, most people don't understand the distinctions, so this will never happen. (Even in reply to your post people keep talking about "decimals", as if the number base is at all relevant here.)

> reals

This is technically impossible. Almost all of the real numbers can't be represented in a computer. The most you can get is the computable reals. But to be able to represent some of those and to do arithmetic on them, you have to use somewhat complicated representations such as Cauchy sequences.

The use cases for computing with exact representations of (computable) irrational numbers are fairly limited (probably mostly restricted to symbolic algebra). In 99% of cases, if you need the square root of 2 that's probably because this comes from some sort of measurement (e.g. you need the diagonal of a square with sides 1), and if it's a measurement, there's going to be an error associated with it anyway and there's no point in insisting that this number that you measured is "exactly" sqrt(2).

This is different from rational (and, in particular, integer) numbers, in which case there are many valid use cases for representing them exactly, e.g. money.

Re: JavaScript Is Weird

#363

Post by hootbootscoot »

ljm wrote: post #339
hootbootscoot wrote: post #223

Earlier quoted context omitted.

gibberish? "JS as a language has nothing to do with browser APIs, why would you judge it based on that?" Excuse me? That is precisely what JS is based upon. Lemme give you a prime example: JS = a single threaded event loop, ON PURPOSE. That directly affected Node.js as an implementation. Your browser has an embedded scripting engine. Embedded, meaning, the source code for your browser includes the scripting language…

And you boil all that down to 'JS is trash'? > JS = a single threaded event loop, ON PURPOSE. That directly affected Node.js as an implementation. That's not a criticism. It's not different to desktop app dev where you try to keep your processing away from the main thread, only it provides an easier interface through async programming. Synchronous = main thread; async = other thread. Amazingly intuitive model. > ES6…

1) I did not originate this "is trash" phrase, but replied to a parent comment you had rather excoriate. I said that Javascript is fine for what it was designed for: a single threaded UI event loop in a web browser. It is NOT good as a high-volume web server, for example. Http has a request and response cycle and is deliberately stateless such that all data goes out of scope and the entire thing can be deconstructed and, poof, no memory overhead nor leaks. It was designed that way, as a protocol.

2) I saw your comment below. You cannot write device drivers in the language of your choice on any of todays popular operating systems, nor on any embedded devices. Device drivers must have low level access to things like memory locations and cpu registers. Such things are not exposed to Javascript and not available. This is not even speaking about performance and garbage collection etc.

Look, Javascript is someones computer program. It can be implemented in very little code: here's an example: https://github.com/cesanta/v7

Languages are not all equal nor do they all function in the same way, and that's not my opinion.

Javascript syntax itself is one thing, and you can certainly feel free to Javascriptify some C++ libraries and make it all look a certain way for specific tasks, while managing things behind the scenes, up to a point... but there is no getting around the fact that SOMEONE and some languages are needed to implement low level systems functionality.

the power of Cython or the Python C FFI is that it allows you to script/glue modular native code.

You then state "C++14 may have been ratified 7 years ago but it's not the target code your build chain spits out"

no, a C++ COMPILER spits out assembler code that then gets assembled and linked into an executable.

The C++ or C code corresponds directly to a given set of assembler instructions which correspond directly to CPU instructions.

You claim that Python programming of microcontrollers is mainstream, but this is not true nor possible. Python SCRIPTING of code modules (that cannot be written in Python) is certainly one way to assemble a system from pre-built legos.

If you refer to knowing what I'm talking about as gatekeeping and egoism, might I suggest that you insist less forcefully in the correctness of incorrect things you state? we could be done with this spat in short order if YOU would refrain from speaking falsehoods. lies.untrue things.

I look forward to your lisp c compiler. make sure that it's 100% lisp from the bottom up, or I'll consider you're having ceded my point. Consider that the lisp you author in has a garbage collection system that lisp cannot have written originally, nor has any semantics for the underlying memory structures of, but hey, I guess if one is committed to pretending that all languages are equal for all tasks, who am I to question ones self-identification with a given language.

Re: JavaScript Is Weird

#364

Post by JoshuaDavid »

Tainnor wrote: post #361
JoshuaDavid wrote: post #312

Earlier quoted context omitted.

"Decimal" usually refers to a data type which is "integer, shifted by a known number of decimal places". So, for example, if you had an amount of money $123.45, you could represent that as a 32-bit floating point number with (sign=0 (positive), exponent=133, mantissa=7792230) which is 123.4499969482421875, but you would probably be better off representing it with a decimal type which represents the number as (integer…

Non-decimal currencies have existed in the past and there are still some remnants: https://en.wikipedia.org/wiki/Non-decimal_currency

Yes, that's a good point. If you try to use decimal for those currencies, you are in for a very similar world of pain as you are by using floats for decimal currencies.

Re: JavaScript Is Weird

#365

Post by jiofih »

hootbootscoot wrote: post #363
ljm wrote: post #339

Earlier quoted context omitted.

And you boil all that down to 'JS is trash'? > JS = a single threaded event loop, ON PURPOSE. That directly affected Node.js as an implementation. That's not a criticism. It's not different to desktop app dev where you try to keep your processing away from the main thread, only it provides an easier interface through async programming. Synchronous = main thread; async = other thread. Amazingly intuitive model. > ES6…

1) I did not originate this "is trash" phrase, but replied to a parent comment you had rather excoriate. I said that Javascript is fine for what it was designed for: a single threaded UI event loop in a web browser. It is NOT good as a high-volume web server, for example. Http has a request and response cycle and is deliberately stateless such that all data goes out of scope and the entire thing can be deconstructed…

> It is NOT good as a high-volume web server, for example

You couldn’t have picked a worse example - your CS major seems to be needing a refresh. NodeJS came to be precisely because V8, single threaded and using an event loop, was GREAT at a high volume web servers. It massively reduced the overhead vs multi-process or thread based web servers and absolutely dominated performance benchmarks and concurrency. We started playing with 1M concurrent connections while you might barely get 100 on Apache a few years earlier. There were other async servers at the time (Tornado, Puma, Netty..) but the async-by-default ecosystem in node was a unique advantage.

Fast forward to today, it’s not an accident that the majority of high-performance web servers now are asynchronous and/or using cooperative multitasking (or even libuv directly, a spin-off of nodejs development): VertX, Actix, h2o, Jetty, go with goroutines, etc. It’s a much more efficient model.

Re: JavaScript Is Weird

#366

Post by pwdisswordfish8 »

viraptor wrote: post #357
pwdisswordfish8 wrote: post #347

Earlier quoted context omitted.

> C will at least give you warning about types For the same reason that, as the saying goes, there is no such thing as a "compiled language", no, "C" doesn't give you a warning about types. The compiler you're using gives you a warning. If you want a typechecking pass over JS, then use a tool that does typechecking. Eschewing with a typechecker and then complaining about the lack of type mismatch warnings, however, m…

Sure, we can go into very true, but specific cases. But in a day to day usage: When you're writing plain JS, you have to do extra work to get type checks. When you're writing plain C, you have to use an unusual environment to not get basic type checks.

So? The majority of the business world does their desktop computing with Microsoft Windows, but it doesn't mean you have to. The same principle applies here. If you don't like your environment, fix it. Choosing not to and then complaining about the result makes little sense.

Re: JavaScript Is Weird

#367

Post by _nub3 »

ranguna wrote: post #356
sli wrote: post #341

Earlier quoted context omitted.

This falls apart the moment you're pulling remote data at runtime. You're right back to defensive programming since there's no more type system to help you at that point.

So you are saying that because we need to do validation in a very specific case, we should just throw the towel and do validations every time? The IO entry point of your code will always be unknown no matter what programming language you are using. In typescript, you do validations in these cases to make sure outside data fits into your type system, from then on (probably about 99% of the rest of the code) won't need…

so when the transpiled typescript is used by the next door 'i know javascript'-1337-hax0r and is fed with some arbitrary data, your wonderful conceptual typed world does not exist anymore and that wonderful code eventually fails, because a simple sanity check was too much.

Re: JavaScript Is Weird

#368

Post by hootbootscoot »

jiofih wrote: post #365
hootbootscoot wrote: post #363

Earlier quoted context omitted.

1) I did not originate this "is trash" phrase, but replied to a parent comment you had rather excoriate. I said that Javascript is fine for what it was designed for: a single threaded UI event loop in a web browser. It is NOT good as a high-volume web server, for example. Http has a request and response cycle and is deliberately stateless such that all data goes out of scope and the entire thing can be deconstructed…

> It is NOT good as a high-volume web server, for example You couldn’t have picked a worse example - your CS major seems to be needing a refresh. NodeJS came to be precisely because V8, single threaded and using an event loop, was GREAT at a high volume web servers. It massively reduced the overhead vs multi-process or thread based web servers and absolutely dominated performance benchmarks and concurrency. We starte…

1) you confuse me with a CS major on another thread. pick the right feud please.

2) "you couldn't have picked a worse example" HAAAA! You are wrong. wrong wrong. A) Do you even know what a memory leak IS and why/how it occurs? B) Did you understand what I said regarding stack allocation and out-of-scope equals "memory gone" and how that fundamentally differs from heap-based allocation as ALL JS OBJECTS ARE!??? you are wasting my time, friend.

you are straight up copying marketing lines from node.js with no apparent understand of what a single threaded event loop even is! (it is a gui system. almost all windows-style apps since 199whatever have an event loops as ONE of it's threads. Open X-code or Visual Studio and make a generic desktop app, and add a button and make it's click handler call a method of something or other. Check a moderately complex audio visual production application for clues on just how many threads one uses and for what purposes are they separate threads, etc.)

You then mention VERTX AND GOROUTINES RIGHT AFTER EXTOLLING THE VIRTUES OF A SINGLE THREADED EVENT LOOP. GO LOOK UP WHAT THOSE 2 SPECIFIC TECHNOLOGIES USE AND DO, VERSUS A SINGLE THREADED EVENT LOOP.

Do note why single core limits exist for single hardware thread execution worlds and stop saying that interleaving tasks on a single execution core is superior to architecting synchronized activity across all cores, and do note that you are primarily referring to CRUD web-dev while positing very erm controversial positions on programming language use-cases.

Node JS is a terrible high-volume web server as all of the alleged virtues you extol are workarounds from the single threaded execution model of what was never designed to be a server language. I will say it again: HTTP is a stateless protocol involving a request (method call) and response (what it returns) it then goes out of scope and disappears. no memory leaks. no heap memory allocation. no malloc. no new, etc. it's just poof gone. got it? this was done on purpose by smart computer people. If you want to run each request as a separate OS process, don't blame HTTP, but the primitives were designed for efficiency.

please DO look up what heap vs stack allocation is. please DO look up what a register vm vs a stack vm is. please DO not confuse scripting or glue code with machine code, as the machine code of your javascript program is precisely the javascript runtime with it's execution paths being puppeted by your script language. you are literally pushing someone elses buttons and calling it computer programming. no offense, that's why it's a high level language not a low one.

when you resort to reductio ad absurdum suggesting assembler as the tool for all programming, you are not engaging with anything I have said or written here, as tools have purposes, not everything is a hammer/nail

in a way, you are not wrong, as a macro-assembler, or C or C++ or Rust or Zig or Nim etc (non garbage collected compiled language capable of outputting machine code as the final target) is the next level up from asm.

Why do you suppose that Chrome is not written in JS but rather largely in C++?

Re: JavaScript Is Weird

#369

Post by nawgz »

_nub3 wrote: post #367
ranguna wrote: post #356

Earlier quoted context omitted.

So you are saying that because we need to do validation in a very specific case, we should just throw the towel and do validations every time? The IO entry point of your code will always be unknown no matter what programming language you are using. In typescript, you do validations in these cases to make sure outside data fits into your type system, from then on (probably about 99% of the rest of the code) won't need…

so when the transpiled typescript is used by the next door 'i know javascript'-1337-hax0r and is fed with some arbitrary data, your wonderful conceptual typed world does not exist anymore and that wonderful code eventually fails, because a simple sanity check was too much.

This seems like a pretty bad-faith comment. This user is not proposing they're building a library, and if they were, it would be reasonable to assume they also would assume to extend the IO protections they discuss to the "IO" points of library - external user input.

Additionally, I think it is safe to say a JavaScript user who grabs a TypeScript library and uses it without importing the types to be misusing the library. Imagine if someone were to have a whole test suite was available to them while they develop, and they opted to never run it. And then they complained to you the tests didn't catch any errors. You would look at them sideways, no? Misuse and poor application (human error) are of course things TypeScript cannot solve.

Re: JavaScript Is Weird

#370

Post by ulisesrmzroche »

bostonsre wrote: post #345
wartijn_ wrote: post #32

Earlier quoted context omitted.

The site does say so in the introduction > Even if you're a JS developer, most of this syntax is probably, and hopefully, not something you use in your daily life. So I think you should look at this site more as something fun you might not have known if you're an js developer than as criticism of js. That being said, the !!"" isn't that weird of a syntax is it? I see and use the double exclamation mark all the time.

Poor frontend devs.. stuff like this has to result in incredibly painful debugging because of assuming code would act one way when it does something else entirely. > the !!"" isn't that weird of a syntax is it? Why would someone say not not empty string in code somewhere? Or do you mean seeing !!var_that_could_have_empty_string isn't too weird?

That's what tests and code review is for. Truth is that if any of this kinda code gets into prod, then you got bigger problems than some arcane JS gotchas.
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