The Nineteenth Byte

#                        Parsing Expression Grammars
# Based on:        A Recognition-Based Syntactic Foundation
#                              - Bryan Ford
#
# Modified slightly to use equals sign, simpler character escapes and fixed
# "-" at end of character class.

# Hierarchical syntax
grammar    = spacing definition+ eof
definition = identifier equals expression
expression = sequence (slash sequence)*
sequence   = prefix*
prefix     = (and / not)? suffix
suffix     = primary (question / star / plus)?

@LeakyNun that is a self-description of PEG

Sherlock9

@LeakyNun what challenge?

Leaky Nun

@Sherlock9 gist.github.com/kckennylau/6a8ae1048e1ee28df8050146555909f3

Sherlock9

How best to regularly check if the comics in our database have updated without getting too slow as we add more and more comics to check?

Doorknob

4:09 AM

Lots of webcomics have RSS feeds

orlp

@LeakyNun I wrote a PEG parser using that specification, and it can parse itself :P

Leaky Nun

:o

orlp

everything works just like regex, except / is ordered choice (instead of |) - it will always first try the first option, then the second option

Sherlock9

@Doorknob That's what I figured but we're not very familiar with RSS

orlp

on top of that, & matches the next thing, but does not consume it

! is the opposite, not matching the next thing, but not consuming it

Mars Ultor

4:11 AM

@Sherlock9 ?

Sherlock9

I figured it's some XML thing, but we're not very familiar with XML either :P

Mars Ultor

...

What language

Many languages have builtin XML parsing

Leaky Nun

@orlp Isn't | also ordered choice?

orlp

@LeakyNun no

there's a crucial difference

compare the regex a*a to the PEG grammar expr = 'a'* 'a'

now let's say I have a string aa

the regex will succesfully match this

the PEG won't

Leaky Nun

@orlp a*+a

orlp

4:17 AM

similarly

op = "+" / "++"

will never choose the second one, because the first one always matches

Leaky Nun

I see

Sp3000

No backtracking in PEG?

orlp

no

or 'sort of'

every operator is greedy

and / will only choose the next possibility if the first one fails

if they all fail, / will fail itself

Leaky Nun

@orlp try my challenge?

orlp

@LeakyNun must it be a function or is an expression also ok?

Leaky Nun

4:23 AM

@orlp an expression is ok

orlp

C, 11 bytes: ' '*' '*'@'

Leaky Nun

Minkolang: "@ "$*N.

not original xd

orlp

didn't see that

doesn't matter

I solved your challenge :P

Sp3000

o_O should probably take out the prints from most of the Python ones then

Leaky Nun

@orlp ok, add the print back in

orlp

4:26 AM

f(){return' '*' '*'@';}

Leaky Nun

gist.github.com/kckennylau/6a8ae1048e1ee28df8050146555909f3

orlp

btw

Mars Ultor

@LeakyNun 0/10 no UGL

orlp

⁹² is invalid

Mars Ultor

@orlp ?

orlp

4:27 AM

those are still numbers in the source code

they might be superscripted numbers, but they're still numbers

Mars Ultor

No, those are Unicode

Sp3000

(the rules are so mixed on that gist I don't even know what's valid or not)

Leaky Nun

ok, I'll change it

@orlp full program

orlp

Python 3: print(-~ord("\uffff"))

Leaky Nun

updated

@orlp updated

Sp3000

4:31 AM

If it's full program then the last one on the gist currently should just be print len(...) since it won't work in Python 3, and JS would need to be changed too (and probably some of the other langs I don't know as well)

orlp

main(){printf("%d",' '*' '*'@');}

Upgoat

Is adding myself to the wheel group insecure?

Leaky Nun

@Sp3000 js has implicit printing

Sp3000

Are you assuming REPL here?

Leaky Nun

sure

Upgoat

4:33 AM

[vihan@vihan ~]$ vim
-bash: vim: command not found

;_;

Mars Ultor

wat

Helka Homba

@Geobits Fair point. I don't really think most Trump supporters are irrational or unintelligent. I do think many have been sort of hedged in to supporting him (which can happen regardless of party or election type), but no, they aren't idiots.

Leaky Nun

@orlp ok now?

gist.github.com/kckennylau/6a8ae1048e1ee28df8050146555909f3

orlp

Pyth, *FCM" @

Alex A.

@Upgoat Not necessarily but I wouldn't exactly recommend it

El'endia Starman

4:37 AM

@Upgoat Wheel group?

Sp3000

If you're assuming REPL then you should probably state that for JS, to emphasise that it's different (I'd point to this, but +16/-6 and the related comments)

Leaky Nun

@orlp hC"\uFFFF

Alex A.

@El'endiaStarman It's one of the permissions groups on Unix-like systems

orlp

@LeakyNun longer :)

El'endia Starman

Huh. Haven't heard of it before. What's it meant for?

Mars Ultor

4:39 AM

@Dennis Wouldn't .container { width: 95vw; } be better for the wide body userscript?

Leaky Nun

@orlp hC"ÿÿ 7 bytes

Alex A.

Wheel (Unix term)

In computing, the term wheel refers to a user account with a wheel bit, a system setting that provides additional special system privileges that empower a user to execute restricted commands that ordinary user accounts cannot access. The term is derived from the slang phrase big wheel, referring to a person with great power or influence. It was first used in this context with regard to the TENEX operating system, later distributed under the name TOPS-20 in the 1960s and early 1970s. The term was adopted by Unix users in the 1980s, due to the movement of operating system developers and users from...

El'endia Starman

...so....superuser?

Sp3000

@orlp Actually, that's 6 UTF bytes with a literal \uffff

Alex A.

Super user is something different on Windows though, isn't it?

Upgoat

4:40 AM

vihan.org

oh ok ._.

Alex A.

Oh no, that's power user...?

Basically admin.

El'endia Starman

Upgoat is on Windows?

Alex A.

Mac OS X

El'endia Starman

I figured we were talking exclusively Unix systems at the moment.

Oh right, Macs also have a Unix base.

Upgoat

@El'endiaStarman I am on Mac, my server is on CentOS

Helka Homba

4:41 AM

@El'endiaStarman *Up

El'endia Starman

Gotcha. Likewise, in fact, except that I'm on Windows. :P

Alex A.

@El'endiaStarman Actually OS X is based on Darwin, which is based on FreeBSD.

El'endia Starman

@HelkaHomba Thanks, Calvin. ;)

@AlexA. FreeBSD isn't Unix?

Alex A.

@El'endiaStarman Yeah I got confused because I thought you were talking about the "power user" mode on Windows

@El'endiaStarman Technically only Unix is Unix

FreeBSD is a Unix-like system

Upgoat

halp, how host file

El'endia Starman

4:42 AM

@Upgoat Welcome them in, ask them if they want anything to eat or drink, etc...

Alex A.

Downvoted and closed as unclear

Helka Homba

@Upgoat UpUpDownDownLeftRightLeftRightBAStartGoat

2

halp

can't find goat key

4:43 AM

what does all this stuff even meen

orlp

@Upgoat it means you have routed vihan.org to yourself

Upgoat

oh no

that sounds bad

orlp

you done goof't

so when you ping vihan.org you basically ping localhost

Upgoat

why isn't my thing working

Alex A.

I think phase could help you if you're having localhost troubles

@Upgoat Sounds like a question for your doctor

orlp

4:44 AM

@Upgoat that's NSFW

Sherlock9

@MarsUltor Well, I'm only really familiar with Python, but that isn't necessarily the best for a Web service

Mars Ultor

@Sherlock9 Web service?

Dennis

@MarsUltor That would push the side bar off the screen. I made it so that the wiki had the same size as in the editor IIRC.

Upgoat

@orlp ...

Sherlock9

@MarsUltor The assignment is to make a Web thing with a database for our database class

Mars Ultor

4:45 AM

@Sherlock9 Hmm

Alex A.

Oh!! @Sherlock9 was it you who asked me to add them to the Steam group?

Mars Ultor

I've used node for that

Sherlock9

@AlexA. Yeah

Alex A.

I was traveling and missed a bunch of chat pings

Sherlock9

I added you on Steam

Mars Ultor

4:46 AM

PHP would work as well

Helka Homba

Quick poll: Best cooking spice?

Sherlock9

@MarsUltor Yes. I am not familiar with Node nor Ruby on Rails and only tried PHP once or twice

orlp

aww it's so fluffy

Mars Ultor

@Sherlock9 ai node && mkdir thing && cd thing && npm init && npm install sails

Then done

Sherlock9

@HelkaHomba Salt. Used in everything, works with everything (in moderation)

Mars Ultor

4:47 AM

Sails handles everything :P

Dr Green Eggs and Ham DJ

Fizzbuzz

Alex A.

@HelkaHomba Definitely depends on the dish

Dr Green Eggs and Ham DJ

Output is slightly wrong due to a bug though. :(

Helka Homba

@orlp is spider fyi to others

Sherlock9

@MarsUltor Hax

orlp

4:47 AM

@HelkaHomba shh and star

Sherlock9

Also, I'm not sure what any of that does

Helka Homba

@Sherlock9 >,> ok, besides salt

Mars Ultor

Oh whoops that's oh-my-zsh, plus ubuntu/zsh

Helka Homba

@AlexA. garlic(powder) works in lots of things

Mars Ultor

basically install node, create a folder, open terminal/cmd in the folder, npm init, npm install --save sails

Alex A.

4:49 AM

Is garlic a spice?

Upgoat

can I use neovim with a remote file? I really despise having to use nano >_>

Helka Homba

@AlexA. garlic powder surely counts

garlic itself, idk

Alex A.

I greatly prefer fresh garlic to garlic powder. I don't really use garlic powder.

@Sherlock9 Group invitation sent!

Sorry for the delay

Helka Homba

@AlexA. lemons + garlic + cornish game hen = amazing

Alex A.

Lemon and garlic is a powerful combo. Add a little fresh cracked black pepper and you're in business.

Sherlock9

4:51 AM

Cloves, because that's what brought the Old World to Asia, and they're from Indonesia :D

orlp

the most powerful combo is still tomato + pesto + mozzarella

Sherlock9

Nutmeg for the same reasons as above

Alex A.

Cardamom is tasty tasterson

Mars Ultor

TIL Anders Kaseorg did Euclid as well

Alex A.

( ͡° ͜ʖ ͡°)

Sherlock9

4:54 AM

The Dutch and the British traded one of the spice islands in the Banda Islands (a smaller archipelago in the east of Indonesia) for New Netherlands and New Amsterdam

Helka Homba

@MarsUltor TIL Anders Kaseorg existed

@Sherlock9 love nutmeg

Mars Ultor

@HelkaHomba He's like a goat thing that answers here occasionally IIRC

Upgoat

vihan.org \o/

Mars Ultor

Or a weird cow thing with blue horns?

Sherlock9

@HelkaHomba So did all of Europe :D en.wikipedia.org/wiki/Nutmeg

Upgoat