@ChrisJester-Young this is also always an eye-opener for people

lambda n: (lambda f: f(f, n))(lambda f, n: f(f, n-1) + f(f, n-2) if n > 1 else 1)

@ChrisJester-Young Is 0 falsy in Racket?

Like can I do (if (% n 15) or do I have to do (if (= (% n 15) 0)

Pretty cool youtube metadata thingy: h3xed.com/blogmedia/youtube-info.php

@ChrisJester-Young or the slightly more difficult to understand but more fundamental

(lambda f: f(f))(lambda f: lambda n: f(f)(n-1) + f(f)(n-2) if n > 1 else 1)

((()()))()))()()()()()())((()))()())((()()

( ͡° ͜ʖ ͡°)

Should I allow tabs for indentation in Cheddar?

@Downgoat no

@quartata that's what I was thinking

@Downgoat Of course.

no

@QPaysTaxes programming languages should promote good practive

@Downgoat no

friendly reminder of google code jam

> Many languages (especially the ones designed for other people) have the attitude of a governess: they try to prevent you from doing things that they think aren't good for you. I like the opposite approach: give the programmer as much control as you can.

strawpoll.me/7318243

^^

@Downgoat either tabs or spaces.... only let one.

Either.

Let the programmer do what suits them best.

If you ban tabs I swear I will not use the language ಠ_ಠ

@El'endiaStarman but then you end up with no standards. Python is an amazing language because it enforces and encourages good programming practices

@CᴏɴᴏʀO'Bʀɪᴇɴ okay, fine, I'll allow tabs

^^

@Downgoat merci :D

@quartata No.

@ChrisJester-Young OK.

@quartata There is only one falsy value in Scheme, and it's #f.

@NathanMerrill s/n amazing//

@QPaysTaxes I'm pretty sure this whitespace stuff in python is an enforcement

should it throw a syntax error or a warning if both indentation are used?

ok, going with syntax error :P

@Downgoat warning yes

@QPaysTaxes Why bother? The syntax isn't from sed.

what should the error message be?

It'd be pointless to include it in conversation anyway.

> Warning: WTF are you doing using both tabs and spaces, you crazy?

Warning: Waffles

@QPaysTaxes that works too...

> Warning: Pick tabs, spaces, or the waffle emoji and stick with it dumbass

@orlp Uh, lemme read.

should I allow waffles for indentation?

@Downgoat Better: "Warning: you will be slapped with a trout if you continue in your wrong practices."

^

It'd be fantastic to have an editor that fixed indentation to whichever style you wanted.

@QPaysTaxes People will find it by looking at the code.

What chars should be allowed in variable names?

@orlp Lemme guess. That's some variant of Y combinator?

@El'endiaStarman obsfucation

strawpoll.me/7318293

@ChrisJester-Young it's in the direction, but it's not proper yet :)

@Downgoat I only said "whales" because if you include BS options you're going to get BS answers. :P

you can't just throw someone the Y combinator in the face and expect them to understand it

^^

XD

turing completeness proof method

*very general

@QPaysTaxes "TCS"?

#lang racket
(define fizzbuzz (lambda (n) (if (= (modulo n 15) 0) "FizzBuzz" (if (= (modulo n 5) 0) "Buzz" (if (= (modulo n 3) 0) "Fizz" (number->string n))))))
(for ([n (in-range 1 100)]) (display (string-append (fizzbuzz n) "\n")))

I made a thing

@QPaysTaxes oic

@QPaysTaxes Computational complexity theory is the specific field for that kinda thing

@quartata noic

@QPaysTaxes Yes

Variable Formatting

@CᴏɴᴏʀO'Bʀɪᴇɴ what do I post

Lower camel case because that's objectively the best

@quartata incorrect

@AlexA. *correct

Doesn't Julia use lowerCamelCase too?

Never

Really?

Yep

Type names are UpperCamelCase and everything else is all lowercase

or snake_case

Snake case is OK

I use that for functions sometimes if I think it looks better

Never for variables though

@AlexA. UserCamelCase is called PascalCase

I've heard both

Sorry to plug Minecraft so much, but this was fun:

@HelkaHomba woah, since when can you fly?!?

@Downgoat Since 1.9.

You can get Elytra from End Ships in the End.

oh

minecraft.gamepedia.com/Elytra

I haven't played since 1.8

@HelkaHomba holy macmadoodles what is that giant crater in the side of the mountain there

Is this at spawn?

Oh wait

It's not.

ppcg mc server?

I was feeling panicky for a second.. I thought something bad had happened to the spawn plateau

A description of how a variable should be parsed, e.g., only alphabetic

@CᴏɴᴏʀO'Bʀɪᴇɴ I submitted [$_\u{L}][$_\u{L}\d]*

is that right?

idk what \u{L} is

regex

I know that.

But isn't \u a unicode escape?

Not in a regex.

@CᴏɴᴏʀO'Bʀɪᴇɴ it is PCRE REGEX

Idk that

Join us :)

@HelkaHomba is the PPCG minecraft server an online server or an offline server?

@Downgoat Online.

D:

I take that to mean you have cracked

@Downgoat If you have a legit Minecraft account you're welcome to join

@quartata Decline to answer :|

@quartata Would you like some feedback on your code? :-)

@ChrisJester-Young Yes I'm sure it looks ugly to a good Scheme programmer

@Downgoat You really should just buy the game... :/ It's a good game and worth the weight money

@quartata if I buy it I will waste all my time playing it

@quartata I'm not saying "ugly", but more...unidiomatic. :-)

I seem to recall there's another function that's better than nesting ifs like that

@quartata Sure, cond.

I also felt a little guilty using a for because I know it's not idiomatic

@quartata for is very idiomatic.

I could map instead probably.

@quartata Do not use map instead.

@ChrisJester-Young It is? I didn't really think it's something you use a lot in functional languages in general

@ChrisJester-Young ok

Lemme see how cond works real quick

@quartata A for is called an eager comprehension. There are variants of this, most notably for/list, which is a list comprehension.

Racket's implementation of for is very, very functional, with no mutation or anything dirty.

Pyth highlighter anyone?

cond is like (cond [cond1 body1] [cond2 body2]... right?

That's probably a lot better

@quartata Yep.

Also Scheme has case, which works like switch in C-like languages.

How can I do a pure else in (cond?

Use else.

Oh well der

#lang racket
(define fizzbuzz (lambda (n) (cond [(= (modulo n 15) 0) "FizzBuzz"] [(= (modulo n 5) 0) "Buzz"] [(= (modulo n 3) 0) "Fizz"] [else (number->string n)])))
(for ([n (in-range 1 100)]) (display (string-append (fizzbuzz n) "\n")))

ahh so much less parens

Are the parens around [n (in-range 1 100)] necessary?

@KennyLau I was working on one for Vim but I haven't had much time for it recently.

@quartata Yes.

OK.

@AlexA. It's fairly simple, because each letter has a fixed arity

Just wondering since there weren't any in the cond clauses

@quartata All right, ready for the rest of my comments, or do you want to do more tidyups first? ;-)

Go right ahead :)

@KennyLau I know. I wasn't doing it based on arity though, just by type of token (operator, constant, string, etc.).

@ChrisJester-Young the Y combinator is a bit more complicated

comb = (lambda c: lambda f: f(lambda x: c(c)(f)(x)))(lambda c: lambda f: f(lambda x: c(c)(f)(x)))

@AlexA. But you would need to use arity to do pyth?

in return, it allows for really nice recursive functions

The #s might be more complicated

020 -> 0 and 20

fib = comb(lambda f: lambda n: f(n-1) + f(n-2) if n > 1 else 1)

@quartata Okay. 1. Use (zero? x) instead of (= x 0). 2. It's okay to return n in the else case instead of coercing it to a string, because in a minute I'll nuke the string-append. 3. You can use displayln to display an object then print a newline. Alternatively you can use (format "~a~%" x) for something more complicated than just printing x and a newline. 4. You have an off-by-one error. (in-range 1 100) counts from 1 to 99 inclusive.

@KennyLau I'm not sure what you mean. All operators are being given the same color.

@orlp Yepyep.

@ChrisJester-Young I know (in-range is inclusive, I only wanted 1 to 99

@AlexA. But we often have nested operators...

I didn't know about (displayln though thanks

and (zero? is nice

@quartata Okay.

@KennyLau I know. It's just basic highlighting, as you would have with any other language. For example, nested for loops in language X are all colored the same color.

@quartata Note that displayln, for, and format are Racketisms and you can't use them in standard Scheme code. That's what I mean about Racket being more batteries-included.

@AlexA. I see.

#lang racket
(define fizzbuzz (lambda (n) (cond [(zero? (modulo n 15)) "FizzBuzz"] [(zero? (modulo n 5)) "Buzz"] [(zero? (modulo n 3)) "Fizz"] [else n])))
(for ([n (in-range 1 100)]) (displayln (fizzbuzz n)))

@ChrisJester-Young Ah

@AlexA. I have an unrefined code here

J2.nm*]sm*C.RcsmsmC@@Qbd,khk,dhd4ZJ:0lhQJJ:0lQJ

@quartata Yep, pretty good. There's one further trick I use in my own version of FizzBuzz, but you're under absolutely no obligation to use it:

@Winny Hey! Haven't seen you around in a while.

(define (fizzbuzz n)
  (case (modulo n 15)
    [(0) "FizzBuzz"]
    [(3 6 9 12) "Fizz"]
    [(5 10) "Buzz"]
    [else n]))

@KennyLau Um, okay. Cool.

J2.nm*]sm*C.RcsmsmC@@Qbd,khk,dhd4ZJ:0lhQJJ:0lQJ
ONOOOOOOOOOOOOOOOOOOOCOOOOOOOOOONCOONOOOOOONOOO

hi @AlexA. nod @ChrisJester-Young

@Winny o/

'\o

@AlexA. O for operator, N for number, C for constant

nice fizzbuzz, using case, never considered that

That's basically what you get for a typical code

Yep

It's not going to be all that useful, just simple.

@AlexA. Might be better if you would highlight 0-arity (numbers + constants) 1-arity 2-arity 3-arity separately

it's great to see fellow racketeers online

@KennyLau I've considered it. Just not sure whether I care enough to do it. :P

I need to come up with a better demonym for that...

@AlexA. As you will.

@Winny Racketball players

@AlexA. :D that makes us sound like health nuts

Haha

@ChrisJester-Young Oh, that's a nice way too.

@Winny Racketeers is the correct term.

Btw @Winny is your avatar from Rocko's Modern Life or something? :P

@Winny I wouldn't really consider myself a "Racketeer" since I just started learning a half-hour ago

@Winny Thanks!

@AlexA. I think it's an 80s or 90s pattern used on cups or something

Oh okay

@quartata :-D

@quartata you're a racketeer in my book :D

@quartata I'd consider you more of a racketball player

@AlexA. I have played racketball once

That's more than I have. How was it?

I used to have a racketball because they're super bouncy and I was like 10 but I didn't have a racket or anything.

idk I think I was also 10 so I can't remember really

I feel like racketball is kind of dangerous for 10-year-olds

Isn't it?

Well, perhaps no more than other sports

Probably. My sister played soccer. I played stay inside.

Stay inside is my favorite sport

I'm super good at it. Professional level, you might say.

@ChrisJester-Young are you guys going to be discussing the problems during the qualifiers?

@AlexA. I suspect this site is full of professionals.

(in the irc challenge?)

@HelkaHomba You're probably right.

I wonder how many of the users here actually like being outside.

I do, just... within reason. :P

@NathanMerrill Hell no.

I like seeing snow from inside the comfort of my home. I don't like being out in it.

Ooh, starting in less than a minute.

its allowed

What is?

google code jam

For me, beer o'clock started a couple minutes ago