Lounge<C++>

@MooingDuck I can't have a rule for qualified_id (an expression), and then have another rule for expression DOT qualified_id (in the expression definition, recursively).

When it expands out, it becomes ambiguous which one the parser should pick.

Schbabako

6:21 AM

@MooingDuck how shall i solve my problem then?

@MooingDuck my code works with dirent.h and i have to use it.

Mooing Duck

@Schbabako it appears that the solution to your problem is to install windows.

@ThePhD we're on the wrong side of me understanding the issue. Can't you merge those into a single rule? "E=I(.I)*" + "E=$E$(.I)*"

I worked out the issue there

ThePhD

@MooingDuck The parser generator doesn't understand regular expressions.

Mooing Duck

definitelyneed two rules

@ThePhD I would expect that you do

ThePhD

Right, but when I split the rule up into...

wilx

@ThePhD Why? Just process the tokens and put them together in the parser.

Mooing Duck

6:25 AM

since I don't know the syntax for whichever parser you're using

ThePhD

E = // binary exprs and stuff
E = I (.I)*
E = E (.I)+

It becomes ambiguous from the last 2 rules

Because you can expand the E out into an I.

And then it matches either the second or third rule

I tried to split it up but couldn't do it without also losing the ability to . off of arbitrary expressions, like (expr).a.b.c

(2+2).sqrt() etc.

Mooing Duck

@ThePhD nono. Third one is E = $E$ (.I)*

ThePhD

Oh. I have to require parens?

Mooing Duck

@ThePhD solves the problem, doesn't it?

well, unless it's a function call

ThePhD

That doesn't make sense for other expression types like func().a.b.c, right?

Maybe I need 4 rules?

Mooing Duck

6:29 AM

@ThePhD replace I with FE=I that also takes function calls?

E->FI->I?

ThePhD

FE = // function call exprs, indexing exprs
E = // binary exprs and crap
E = I ( . I )*
E = FE ( . I )*

Mooing Duck

I think that just shifts the ambiguity to FI.

@ThePhD yeah, that

ThePhD

Oh, and a fifth rule

Mooing Duck

I think that's still probably an issue though, because a function call expr probablybegins with an identifier

ThePhD

E = \( E \) ( . I ) *

Anything else that could go wrong...?

wilx

6:32 AM

Hm.....

Mooing Duck

@ThePhD does your syntax allow E = FE ( . E)*? depending on things, that may or may not be simpler

ThePhD

I mean. I think I'd need a few more rules.

Like, for literals and stuff

2.pow(12);

Shit my grammar is about to get super complicated.

wilx

You are doing it wrong... IMHO...

Mooing Duck

@ThePhD make a V (values) that is composed of functions, identifiers, literals, etc, and just use that

wilx

You need to figure out a way to have the grammar to be a bit deeper.

Mooing Duck

6:39 AM

@ThePhD I think a goal might be for nonterminals to either do interesting things or have multiple rules, but not both

wilx

@ThePhD
SE -- statement expression, i.e., some top level expression
E -- binary expressions
I -- ID expression, e.g., A.B.C

SE = I
I = E
I = E.I -- change the left/right recursion to your liking
E = ... -- whatever is binary expressions

Mooing Duck

@wilx see, that's way better

@wilx except don't use I because I assume I=identifier, which no longer applies to that grammar

wilx

@MooingDuck I was not reading the whole conversation. I just woke up. :) The point is I would approach this similarly to how normal arithmetic expressions grammar is done with the higher precedence operations lower in the grammar and with the recursive rules.

ThePhD

7:11 AM

> one shift-reduce conflict

SHHHIIIT

So CLOooSosoSOSeeee.

YEEES

IT WORKS

Well, okay. It compiles without error**

Ahhhhnnn the rules are finally without problem

Now to see if it works on source code.

Ahhhh it parses even the new literals so goood.

@wilx @MooingDuck Thanks for helping me get that straight in my head.

Buh.

Functional programming sort of ruins me.

Every time I need to have a new type "propogate" through one of my top-level functions I have to go deliberately pass it down so I can mutate it.

So now I have this veritable leviathan of a function signature taking symbollist, typelist, ast_definitionlist, ...

I just want some mutable variables without the crapshoot syntax.

Telkitty

7:41 AM

in case you need entertainment

Mysticial

@Borgleader

-26

Q: Ever since stack overflow introduced jobs I keep getting downvoted

Why is stack overflow the only social media website in existence that allows down-voting? Ever since stack overflow introduced jobs, I feel like people are adopting a covert-aggressive mentality when it comes to answering questions. I've asked several questions about backbonejs, vuejs, and so on,...

ThePhD

@Mysticial Buahaha, Shogs answer.

Telkitty

7:58 AM

This account is temporarily suspended. The suspension period ends on Dec 13 '17 at 5:19.

 Communities (4)

 Stack Overflow 1 1 17
 WordPress Development 1 1 1
 Mathematics 1 1 1
 Programming Puzzles & Code Golf 1 1 1

I am all suspicious ...

imagine trollng while wearing someone else's picture as your avatar

rightfold

8:16 AM

> backbone and vuejs

> not incompetent

wilx

Is there a way to defeat HTTPS SSL decryption scheme that my company has just deployed?

Shubham

8:34 AM

What should I do if a very high rated SO user comments on my answer and I don't understand what he is trying to say? We both answered on a question and our answer differs. I answered yes and he answered No.

Should I delete my answer?

ThePhD

Do you know if your answer is right?

Shubham

I am not sure now. I think we are talking on different things. His answer is too technical and mine is too naive.

2

One that I read from some other noob blog.

2

wilx

@Shubham No, until you understand why it is wrong. If you know it is wrong and why, then delete your wrong answer. IMHO.

Shubham

8:51 AM

@wix @ThePhD I have asked for some clarification from him. I have to know whether I am right or wrong.

Rerito

sup badlets

Mikhail

@wilx vpn?

wilx

@Mikhail That is probably not doable. Meh. This sucks.

Mikhail

Thinking outside the box you can write a bot that generates a ton of fake traffic, then you can say claim the bot was browsing those porn sites, and not you...

thecoshman

oooh, the woahs of running too mnay VMs... so little ram left for host :'(

Mikhail

9:02 AM

I think vmware has some stuff that lets you share RAM?

With memory sharing, a workload often consumes less memory than it would when running on a physical machine. As a result, the system can support higher levels of overcommitment efficiently. The amount of memory saved by memory sharing is highly dependent on workload characteristics. A workload consisting of many nearly-identical virtual machines may free up more than 30 percent of memory, while a more diverse workload may result in savings of less than 5 percent of memory.

Does it just checksum each page? Sounds computationally intensive...

thecoshman

virtualbox :P

main problem is having loads of chrome tabs open :P

Mikhail

Darn, I've been spending hours trying to figure out how to paradigmatic GUI design with Qt. How do people actual learn this stuff?

rightfold

@wilx What is that?

thecoshman

ergh... and snow it begins... websites are deploying snow fall effects

wilx

@rightfold Some transparent proxy decrypts SSL and inspects it so that we are not leaking sensitive information to social sites, supposedly.

@Mikhail Practice? :)

rightfold

9:14 AM

> This email was sent to: [email protected]

lol Stansted Airport newsletter

@wilx That sounds illegal.

thecoshman

@wilx well that's total bullshit

Rerito

@wilx Unfortunately no

Their routers must be properly configured to bounce the trafic they receive through the proxy

rightfold

@wilx Do you use Wi-Fi? If so, use your phone as a hotspot and work over 4G.

Rerito

^^^ that's the only way

this or turning your phone into an usb modem

Mikhail

Jjust have your local ISP install a router in your cubicle....

wilx

9:19 AM

@rightfold Well, that is probably against the rules as well. However, I do not have a rate that could sustain my habits over 4G for more than an hour. :)

@Mikhail Haha. :D

thecoshman

@Mikhail I want an rainbow isp :)

@wilx ah, are you using your work internet for thins they rightly would not be happy with?

wilx

@thecoshman Is watching YT videos that? :(

rightfold

@wilx Also ask about the security risks of such proxies on Information Security. :P

Mikhail

0

Q: How can I safely store a password in a .class file?

I have some .java files containing some password variables, and these variables have values: String password = "xyz"; Now after run, when I open the .class file, it contains those passwords. How can I store my password somewhere safe? I don't want to use DB for storing.

java secure-coding

nice :-)

rightfold

lol

> I'm not a java developer, naturally I work with C#

yeah, C# and Java are totally different

Mikhail

9:24 AM

The real trick is attach the debugger the moment the decrypted password is used.

thecoshman

@wilx potentially... probably that grey area where they can't out right say it's 'ok' but they don't mind really as long as you don't take piss

Telkitty

Sitting under bright lamp, got bitten by mozzie

Telkitty

9:40 AM

Still getting used to this new tablet

It disconnects itself every 5 minutes or so

milleniumbug

@wilx Don't connect through their network

You may try running a VPN, but in general, it's better if you simply treat whatever passes through enterprise network as potentially seen by your employer.

Griwes

My bank's account page's SSL cert recently stopped validating over the company network. :|

Abyx

@Griwes you mean it's not EV? check its cert chain

rightfold

@Ven I want to learn JCL

fredoverflow

> I think that exceptions are the worst feature in C++, because it just causes memory leaks. All the code I write uses an int or enum to return an error code.

6

@rightfold Well yeah, Java uses -> for Lambdas, whereas C# uses => IIRC!

Borgleader

10:02 AM

@Mysticial Oh my lord that is an impressive amount of butthurt.

@Mysticial hahaha, what

rightfold

10:18 AM

Exceptions are one of the worst features of C++.

As are all the other features that cause a lack of totality, purity, and/or parametricity.

0

A: When is return by value ok?

The Thumb rules regarding return values in C++ are: never return a reference to a local variable never return a pointer to a local variable don't return a value using move semantics as for (3) - This is a known concern with C++ - we all learned that when an object returns by value - it activa...

WTF

> don't return a value using move semantics

> we all learned that when an object returns by value - it activates the copy constructor. this is theoretically true, but practically wrong

Why are any of these answers upvoted is beyond me

TIL you can burn water with fluorine.

Rerito

10:38 AM

@rightfold RVO takes place even when optimizations are turned off right?

Griwes

11:03 AM

@rightfold kek

starmole

11:17 AM

Random c++ question: do iterators have to always point to some data? is it ok to implement an n-d loop as an iterator?

Cheuk Kin Sing

11:39 AM

that's called a generator

Morwenn

11:57 AM

That's called a genderator.

набиячлэвэли

TRIGGERED

Morwenn

Coming from me? :p

набиячлэвэли

That's the joke :P

@rightfold You just need high temp and water will burn in and of itself

Morwenn

I could trigger many trans people, but mostly because they often trigger my inner feminist x)

набиячлэвэли

Remember how it's composed of Hydrogen and Oxygen? Be a shame if somethin'd... happen to that bond

Ramy

12:29 PM

0

Q: Python module for longlong types

I'm trying to make a int64_t module for python because python doesn't have a long long type. I found one in ctypes but I can't use it. So, I have embedded an intro in my application so the best way is to create a module that returns int64_t from c++. PyObject *Py_int64_t(PyObject *poSelf, PyObje...

python c++

Telkitty

1:05 PM

Iguana vs Snakes - Planet Earth II

►

absolutely amazing ...

but not ideal if you are afraid of snakes

rightfold

Interactive echo lol

Ven

Hi

Whoops. 2pm.

wilx

1:31 PM

TIL the expression "Eifel Towering"

thecoshman

1:46 PM

Any chance any you handy with google sheets? Trying to avoid duplicating logic

Ven

2:05 PM

lol google sheets

I gave on "google office" a long time ago.

Telkitty

now, think about it, most people are hoarders - they like to hoard money if they could ...

thecoshman

'gave up on'?

Rerito

@Ven wesh frer yen a qui kiff le son de leur voix ici

Ven

@Rerito ? t'as pas juste bloqué le keumé ?

@thecoshman too buggy too unreliable too inconsistent

Rerito

@Ven I need my daily dose of nonsense

Morwenn

2:18 PM

Makes sense.

Ven

hah!

Rerito

serieux ca vous rappelle pas les keumés qui font leur truc sur la réussite toussa genre moi jsuis trop successful (l of shit)

Morwenn

I mostly avoid watching those kinds of talks.

They're generally booooooring.

thecoshman

@Ven only issue I've had with google sheets is lack of functions, and that'a only really just making it more complex to do things

but I recently learned that they have a function called filter that does a lot of what I've want for a long time

Rerito

2:37 PM

I'm refactoring an old piece of code

The guy who wrote it was clueless about vector

raw pointers everywhere it's so infuriating

(or one of those folks that are convinced raw pointers mean better purrformance)

sehe

3:12 PM

@StackedCrooked it's down, from here

That was quick

Actually, just veereey slow

rightfold

@sehe do you know JCL?

sehe

Sounds familiar. What is it again

Java Class Library?

Either that or some kind of hardware command language

wilx

@rightfold Java commons logging? :)

Or was that something else?

sehe

@rightfold Ah. Good old COBOL smell on that. I might have seen it because people asked to parse it (on the mailing list or SO)

rightfold

@wilx Job Control Language

wilx

3:20 PM

@rightfold Eeek! Mainframes are evil even though this company profits on them greatly.

Ven

yup, COBOLish stuff.

I often stumbled on CL when I was learning COBOL>

rightfold

@sehe I want to learn JCL.

I think I will check out Hercules mainframe emulator.

sehe

you're weird

Etienne de Martel

That is one shitty answer.

rightfold

@sehe bitch please

% cat www/**/*.php | awk '{ ll = length($0); l = l < ll ? ll : l } END { print l }'
1290

@sehe It's indeed not normal to be curious. Hence most people aren't. And that's why everything is shit.

sehe

3:29 PM

Curious is one thing :)

I'm always curious but I need a goal before spending time. Because I'm done wasting it

rightfold

Goal is knowledge.

sehe

I think that's a mistake.

I think understanding is a better goal.

rightfold

6

Jerry Coffin

@sehe I'd mostly agree. There is a degree to which you need to learn some basic facts as a framework for understanding, but in this case that's (at least mostly) inapplicable. JCL isn't really a language at all--it's just a collection of mistakes, mashed together into a big ball of mud.

4

Rerito

@EtiennedeMartel Considering the question is tagged lazy-loading, I find it appropriate

Griwes

3:39 PM

> All lines except for in-stream input (see below) have to begin with a slash "/", and all lines which the operating system processes have to begin with two slashes // - always starting in the first column.

lol

thecoshman

So... could anyone spare me some time and let me know of any maven artifact repositories (like Nexus or Artifcatory) that allow you to configure a proxy that can automatically pull things into the proxy, rather than have to wait to be requested. With out this, I get issue with large artifacts; the proxy starts to download from the source but the main client times-out waiting for the proxy to begin the download to the client. Maybe something that allows the proxy to up/download in parrallel

Bartek Banachewicz

I'm provisioning my server

Christmas came early this year

also idrac is super great

wilx

@BartekBanachewicz Why do you need a server?

Ven

@rightfold you don't need that ($0).

Bartek Banachewicz

@wilx for my team

@fredoverflow he's right

oookey I suppose I do want LVM

Callionymus neptunius

3:52 PM

hi bartek

R. Martinho Fernandes

@BartekBanachewicz Sounds like an XY problem :P

Bartek Banachewicz

@R.MartinhoFernandes it was the default option!!!

@Callionymusneptunius hi. Do I know you?

Callionymus neptunius

@BartekBanachewicz you may

Bartek Banachewicz

@R.MartinhoFernandes I just need one big partion I guess, nothing fancy

1.2TiB total, it's in RAID 10

this is super exciting

R. Martinho Fernandes

lol

Famous last words.

Bartek Banachewicz

4:03 PM

:D

what's the worst that could happen

ueh it boots foreeeeveeer

the installation is finished anyway

Cheuk Kin Sing

@sehe What's the difference between knowledge and understanding? :)

Bartek Banachewicz

yay I'm in

KiB Mem : 74218864 total, 73608472 free,

:3

i can run SO MUCH STUFF

Cheuk Kin Sing

never understood why they don't report units in a more human way

Bartek Banachewicz

72GB

Cheuk Kin Sing

might as well report in bytes, just as useful

@BartekBanachewicz wrong

74.2 GB, 70.8 GiB

thecoshman

4:13 PM

@CheukKinSing because humans aren't the normal users most of the time

Cheuk Kin Sing

@thecoshman are you subtly implying linux users are non-human

Rerito

@CheukKinSing Oh nice one

Bartek Banachewicz

@CheukKinSing yawn

SO MUCH STUFF

VermillionAzure

WHAT IS UP

Bartek Banachewicz

ok I need git

VermillionAzure

4:16 PM

@BartekBanachewicz Yo

Rerito

@BartekBanachewicz There, have RTC :D

Share my suffering

Bartek Banachewicz

@VermillionAzure git gut

VermillionAzure

@CheukKinSing lol

@BartekBanachewicz wat

Rerito

RTC = Ruine Ton Code /cc @CheukKinSing

Bartek Banachewicz

I wonder if I should make my shell start in tmux by default

VermillionAzure

4:17 PM

Did you mean _git gui_?

@BartekBanachewicz Could be a good idea

Griwes

Oh look, my two favorite plonked people are having a conversation! How cute! :D

2

Bartek Banachewicz

oh apparently git is installed by deafult

Cheuk Kin Sing

@Rerito Rase Tes Couilles ?

Bartek Banachewicz

anyway I have ssh auth already

VermillionAzure

@Griwes Hey Ram

Rerito

4:19 PM

Star Wars: Pole Ones

thecoshman

@BartekBanachewicz what OS did you install o_0

VermillionAzure

So uh

Exceptions: Good or bad?

Rerito

Good, but there are exceptions... Huehuehuehue

Ell

ggod

Bartek Banachewicz

@thecoshman ubuntu server

@VermillionAzure bad

VermillionAzure

4:21 PM

Ugh

I can't decide anymore

Cheuk Kin Sing

@BartekBanachewicz can't tell if serious or joking

VermillionAzure

Maybe I should just move onto Rust or Haskell or Java already

Just make it easier on myself

or harder.

thecoshman

@BartekBanachewicz huh... I guess it makes sense to have git by default...

Kotlin > Java

@CheukKinSing ah, hi cicada

Bartek Banachewicz

@CheukKinSing serious?

Lalaland

@VermillionAzure Move onto those from what? C++?

Bartek Banachewicz

4:23 PM

what's the problem with that

VermillionAzure

@Lalaland I think so

Bartek Banachewicz

also is there a default linux group for "human" users?

VermillionAzure

I've been doing SICP recently. I don't like it but it's my senior project now so BAH.

And now I'm thinking of playing around with Rust and Haskell for good measure

Get some of that theoretical functional programming and type systems in the brain

Bartek Banachewicz

bba adm cdrom sudo dip plugdev lxd libvirtd lpadmin sambashare

I guess I need a new group

Lalaland

Haskell is interesting. Especially when you try to write something substantial in it.

Rust isn't that interesting compared to C++. You code mostly the same in Rust as you would in C++.

Just with more verification.

Cheuk Kin Sing

4:25 PM

My favorite part of using Haskell is when you throw it away and use a real language instead.

sehe

@CheukKinSing You can know a lot of facts without understanding. You can understand things without knowing a lot of the facts. Often the facts don't help with the fundamental understanding (they just help check the understanding)

Cheuk Kin Sing

@sehe What I meant is that one without the other is pointless.

There is no understanding without knowledge and knowledge without understanding has no value.

Believe my lifelong experience. (Maybe you too one day will understand.)

Bartek Banachewicz

Cheuk Kin Sing

My screen real estate is being robbed by low quality mems

Bartek Banachewicz

serves you about right

ugh our git repo is too fat

Cheuk Kin Sing

4:27 PM

maybe you shouldn't have tracked your mom in the first place

sehe

@CheukKinSing You have never been properly taught. There is no trust without checking, but learning without trusting is severely limiting (in fact, I think it's impossible, and even you are guilty to accepting vast amounts of "understanding" without knowledge).

Point is, not all things that can be understood merit a deep understanding. Different things matter to different people of course.

Cheuk Kin Sing

@sehe If I can't convince you then maybe Aldous Huxley can

sehe

I don't think you'll find much contradiction. Care to reread/spot the original context?

thecoshman

@BartekBanachewicz 'too fat'?

@BartekBanachewicz generally speaking, when you make a new users, you make a new group for just that user, with the same name... and only add that user to more groups as you require it

sehe

I don't think it's contradictory to say that understanding is often the higher goal than the knowledge. That doesn't at all imply knowledge is worthless or "not required".

Rerito

4:36 PM

Most people know about aggregate initialization, but do they understand @CheukKinSing? Do they???

Callionymus neptunius

I do

I understand cicada

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