Carlos Galdino carlosgaldino

"A type system is a tractable syntactic method for proving the absence of certain program behaviors by classifying phrases according to the kinds of values they compute." - Pierce, TAPL

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

ElixirConf 2014

Dave Thomas—Opening Keynote

Twitter | Slides

Think different(ly)

Get out of your rut and learn new ways to think.

"Consensus is impossible" is a gloss for "there's always an execution that doesn't terminate".

Once you've internalized that you can't distinguish slow nodes from dead nodes, how do you deal with that?

"When you're engaged in a battle of wits with a Sicilian and death is on the line, you certainly need to think about epistemic logic."

A correct distributed program achieves (nontrivial) distributed property X. So we need to ask:

is X even attainable?
what's the cheapest* protocol that gets me X? (* according to some cost metric)

Parsing CSS file with monadic parser in Clojure

Inspired by "Parsing CSS with Parsec".

Just quick notes and code that you can play with in REPL.

By @kachayev

0. Intro

Channels Are Not Enough

... or Why Pipelining Is Not That Easy

Golang Concurrency Patterns for brave and smart.

By @kachayev

Intro

Yosemite upgrade notes

From a (mostly) Ruby on Rails developer.

After doing the below everything seems to work (some of it worked before doing anything), including Ruby, Gems, RVM, Homebrew, VirtualBox/Vagrant VMs, Pow, tmux, git, vim.

Did a full-disk backup that I can restore from
Moved out /usr/local to avoid super slow install, per option 1 in https://jimlindley.com/blog/yosemite-upgrade-homebrew-tips/: sudo mv /usr/local ~/local
Upgraded to Yosemite
Restored /usr/local, per option 1 in https://jimlindley.com/blog/yosemite-upgrade-homebrew-tips/: sudo mv ~/local /usr

This blog post series has moved here.

You might also be interested in the 2016 version.

A Quick and Dirty Lens primer

Why does Lens exist? Well, Haskell records suck, for a number of reasons. I will enumerate them using this sample record.

data User = User { login    :: Text
                 , password :: ByteString
                 , email    :: Text
                 , created  :: UTCTime
 }

	# List of all the valid pdf URLs ever posted to the #Clojure IRC channel.
	#
	# Many of them are interesting CS papers others are not that useful. What I've done:
	#
	# 1. crawled an IRC history archive for the channel
	# 2. extract pdf list in a file with: grep -riIohE 'https?://[^[:space:]]+pdf' * > pdf-links.txt
	# 3. remove dupes: cat pdf-links.txt \| sort \| uniq > pdf-links-uniq.txt
	# 4. filter only HTTP 200: cat pdf-links-uniq.txt \| xargs curl -o /dev/null --connect-timeout 2 --silent --head --write-out '%{http_code} %{url_effective}\n' \| grep "^200" > valid-pdf-links.txt
	#
	# Now your choice to download them all or not. If you want, use: cat valid-pdf-links.txt \| awk '{print $2}' \| xargs wget