Holm @judofyr@ruby.social

Me: How do I work with currency?

Ruby: Just use BigDecimal.

JS: Deal with floating point math edge cases on every operation you do, forever.

A Noble Circle is free for PI Day. Hope you enjoy it. It is best played with sound on, and with a loved one. https://itunes.apple.com/pl/app/a-noble-circle/id977865620?mt=8

Hey all! So who’s going to RailsConf this year?

#introductions Hi all, my name is Rodrigo and I've been developing with Ruby for 4 years now.
Lately I've been using Hanami at work and in some personal projects, but I really want to get back to develop some stuff with Rails again.

A script to run tests changed since master, pretty handy when checking PRs:

test_runner = File.exists?("Gemfile") ? "bundle exec " : ""
test_runner += if File.exists?("config/application.rb")
"rails test"
elsif File.directory?("spec")
"rspec"
elsif File.directory?("test")
"ruby -Itest"
else
"ruby"
end
changed_test_files = `git log --name-only --pretty=oneline --full-index master..HEAD`.split.select { |f| f =~ /\Atest|spec/ }
exec "#{test_runner} #{changed_test_files.join(' ')}"

really interesting article about how to log: https://apenwarr.ca/log/20190216

Starting to write up some blog posts on generally useful programming topics. Partially to try to solidify my own knowledge - it's tough to write about a subject you only have a fuzzy understanding of. Hopefully it will be useful to someone else down the line as well!

First one is a #regex intro, feedback welcome:

https://edsaav.com/regular-expressions

How ERB uses `Binding` objects:

class DiyErb
def initialize(template)
@template = template
end

def result(binding)
@template.gsub(/<%=(.+?)%>/) do
binding.eval($1)
end
end
end

https://blog.appsignal.com/2019/01/08/ruby-magic-bindings-and-lexical-scope.html

I’d love to see better examples of using `#tap`, but I’ve mostly seen it used to refactor this:

metadata = {}
metadata[:id] = user.id if user
metadata

That’s explicit. It creates a hash, adds a value if a condition is true, then returns the hash.

With `#tap`, the code is more difficult to read, and requires the next person to know what `#tap` does (“yields x to the block, and then returns x.”). 🤷‍♀️

{}.tap do |metadata|
metadata[:id] = user.id if user
end

Ruby snippet to print a line of code and its result:

```
def debug(&block)
puts block.source.strip
result = http://block.call
puts "# => #{result}"
result
end

debug { 1 + 2 }
```

RubyGems 3 released! https://blog.rubygems.org/2018/12/19/3.0.0-released.html

looks like Ruby 2.6 on Christmas is landing with RubyGems 3 and Bundler 2

Exciting!