It's Not Ruby, But…

Ruby is a great programming language, but it’s not the only one. This week, we’ll be talking about different programming languages, what they’re good for, how they differ from Ruby, and why you might want to use them.

Transcript

1. It's Not Ruby, But… Miami Ruby Brigade March 19, 2018
2. It's Not Ruby, But… • Polyglot Culture • Skills & Tools
 • Python • Elixir • Rust • Crystal
3. Polyglot Culture vs. Contempt Culture
4. Polyglot Culture Programming languages are cool and it's good there are like a million of 'em
5. Polyglot Culture • Some are fun and are good to learn and crib concepts and ideas from • Some are really useful for a specific task • Some are pretty good at lots of things
6. Polyglot Culture • No one programming language is good at everything • When a language is the best at one thing it's frequently really bad outside that
7. Polyglot Culture So just learn lots
8. Contempt Culture • it's real bad • makes people feel bad about their valuable time spent learning "contemptible" languages
9. Contempt Culture • disproportionately targets languages used by people in more-marginalized groups
10. Polyglot Culture vs. Contempt Culture • i've done php, java, and javascript professionally • and i enjoyed and learned from them all
11. Polyglot Culture vs. Contempt Culture • it's okay to not like or avoid languages • but your reasons aren't everyone's reasons and your choices aren't everyone's choices
12. Value and honor peoples' decisions to use what they do
13. It's Not Ruby, But… • Polyglot Culture • Skills & Tools
 • Python • Elixir • Rust • Crystal
14. Skills Programming is hard
15. Skills • Getting a handle on a single programming language is a difficult proposition • Learning a second language is also hard • Being able to switch languages on the same project is even harder
16. Skills • so gj everyone that can switch from ruby to js without forgetting: • parens around arguments • return statements • how prototypes work
17. Skills • the more languages you learn, the easier it gets • especially if those languages are related somehow
18. Tools • lots of stuff in ruby is available for other languages • package managers • syntax highlighting for your editor
19. Tools • sometimes it's not great, depending on how fresh the language is • sometimes it's not great because the language just grew differently
20. It's Not Ruby, But… • Polyglot Culture • Skills & Tools
 • Python • Elixir • Rust • Crystal
21. Python • it's an interpreted object-oriented language from the '90s • Inspired Ruby!
22. Python • scientific computing • program analysis • "computer hacking"
23. Python • angr • binary ninja • pwntools
24. import angr 
 import simuvex 
 import binaryninja 
 
 bv = binaryninja.BinaryViewType['ELF'].open('magic') 
 bv.update_analysis_and_wait() 
 
 sum_string = "sum is %ld\n" 
 strings = bv.get_strings() 
 sum_ref = [r for r in strings if 
 sum_string == bv.read(r.start, r.length)][0] 
 code_ref = bv.get_code_refs(sum_ref.start)[0] 
 main_start = bv.get_previous_function_start_before(code_ref.address) 
 main_func = bv.get_function_at(main_start) 
 main_return = [o for o in main_func.low_level_il.basic_blocks[0] if 
 binaryninja.enums.LowLevelILOperation.LLIL_RET == o.operation][0] 
 
 
 proj = angr.Project('magic', 
 load_options={'auto_load_libs': False}) 
 add_options={simuvex.o.BYPASS_UNSUPPORTED_SYSCALL} 
 path_group = proj.factory.path_group(threads=1) 
 path_group.explore(find=main_return.address) 
 
 print path_group.found[0].state.posix.dumps(0) 
 print path_group.found[0].state.posix.dumps(1)
25. Why Python? • Libraries that aren't available in Ruby • Or aren't as good in Ruby • Documentation to do a thing that doesn't exist for Ruby
26. Big Changes in Python • mandatory good indent style • without parens you get the function as a value instead of calling it • you need to return to return a value
27. Big Changes in Python • global functions that call awkwardly-named methods instead of just methods • len(collection) or collection.__len__() • instead of collection.length()
28. Big Changes in Python • Python package management developed parallel but independent from Ruby's • octopus eyes work a lot like human eyes but they evolved 'em completely differently
29. Big Changes in Python • python 2 vs. python 3 • use python 3 when you can
30. Small Changes in Python • nil is None, true is True, false is False • it's already installed with a whole pile of libraries • a lot of Linux distros use it
31. It's Not Ruby, But… • Polyglot Culture • Skills & Tools
 • Python • Elixir • Rust • Crystal
32. Elixir • erlang-like language with ruby syntax • made by Rails users
33. Elixir • i already knew Ruby and Erlang so i picked up Elixir in a weekend
34. It's Not Ruby, But… • Polyglot Culture • Skills & Tools
 • Python • Elixir • Rust • Crystal
35. Rust • Mozilla made Rust because C++ doesn't do everything they need to • new by PL standards, first showed up in 2010
36. Rust • a lot of the tooling was built by Ruby users
37. Rust • you will hear people complain about the compiler being really picky • working as intended
38. In most browsers, it would be hard to get this right. Parallelism is a known hard problem, and the CSS engine is very complex. It’s also sitting between the two other most complex parts of the rendering engine — the DOM and layout. So it would be easy to introduce a bug, and parallelism can result in bugs that are very hard to track down, called data races. […] With Rust, you can statically verify that you don’t have data races. This means you avoid tricky-to-debug bugs by just not letting them into your code in the first place. The compiler won’t let you do it. https:/ /hacks.mozilla.org/2017/08/inside-a-super-fast-css-engine-quantum-css-aka-stylo/
39. Rust Projects I've Done • sinatra-like webapps that call shell scripts • programs that get hacked but only the right way
40. use std::net::UdpSocket; 
 
 fn main() { 
 let socket = UdpSocket::bind("0.0.0.0:1337"). 
 expect("failed to bind udp socket"); 
 
 socket. 
 set_read_timeout(None). 
 expect("couldn't set forever timeout"); 
 
 loop { 
 let mut buf: [u8; 32] = [0; 32]; 
 
 let (amt, src) = socket. 
 recv_from(&mut buf). 
 expect("failed to recv"); 
 
 assert!(amt == 32, "recvd {}, wanted 32", amt); 
 
 let expectation = [56, 55, 53, 53, 49, 99]; 
 
 if buf == expectation { 
 let reply ="nice!".as_bytes(); 
 
 socket. 
 send_to(reply, &src). 
 expect("failed to reply, rats"); 
 } 
 } 
 } 
 

41. Rust stuff worth looking at • Helix: use rust (instead of c) to write ruby modules
42. Twitter to Mastodon • Nintendo Switch posts screenshots and videos to twitter and facebook • I want those on my Mastodon account
43. Twitter to Mastodon • watch my tweets for #NintendoSwitch on the twitter streaming API • pick the best media version to post to mastodon • download the media • upload it to mastodon • post the toot
44. Twitter to Mastodon • honestly it'd be a ruby program • want to fit it in spare memory on an ec2 instance • and not think too hard about it
45. switch-tweet-copier • got to the media picker before i got tied up in types and compiler errors • JSON's type system vs. Rust's type system
46. It's Not Ruby, But… • Polyglot Culture • Skills & Tools
 • Python • Elixir • Rust • Crystal
47. Crystal • what if ruby but compiled to native bytecode
48. private def process_media(tweet) 
 blank = [] of ::Mastodon::Entities::Attachment 
 extended_entities = tweet.extended_entities 
 return blank if extended_entities.nil? 
 media = extended_entities.media 
 return blank if media.nil? 
 
 media.map do |medium| 
 pp medium.type 
 
 case medium.type 
 when "video" 
 process_video(medium) 
 when "photo" 
 process_photo(medium) 
 else 
 nil 
 end 
 end.compact 
 end 

49. Crystal • I finished the project :3 • Only had to update a bunch of libraries "shards" by hands
50. Changes in Crystal • "ruby" is "crystal" • "gems" are "shards" • "bundler" is built in
51. Changes in Crystal • type annotations • Not a huge community
52. It's Not Ruby, But… • Polyglot Culture • Skills & Tools
 • Python • Elixir • Rust • Crystal
53. Conclusions • learn more languages • don't hate • lots of good languages for different tasks