Diogo Felix onlurking

Web Scraping Workshop

Using Requests and Beautiful Soup, with the most recent Beautiful Soup 4 docs.

Getting Started

Install our tools (preferably in a new virtualenv):

pip install beautifulsoup4

tmux cheatsheet

As configured in my dotfiles.

start new:

tmux

start new with session name:

DEPRECATED

Please see: https://github.com/kevinSuttle/html-meta-tags, thanks for the idea @dandv!

Copied from http://code.lancepollard.com/complete-list-of-html-meta-tags/

Basic HTML Meta Tags

tmux cheat sheet

(C-x means ctrl+x, M-x means alt+x)

Prefix key

The default prefix is C-b. If you (or your muscle memory) prefer C-a, you need to add this to ~/.tmux.conf:

remap prefix to Control + a

tmux shortcuts & cheatsheet

start new:

tmux

start new with session name:

tmux new -s myname

Partial Evaluation, Futamura Projection And Their Applications

What Partial Evaluation Is?

Partial evaluation means to fix some variables in the given code before execution. With a traditional implementation of a compiler or an interpreter, all variables are replaced with its value on each evaluation of that variable. This is because a variable can change at any timing. This is, however, not always true in actual applications. Almost all of large applications has setting variables and data

Locate the section for your github remote in the .git/config file. It looks like this:

[remote "origin"]
	fetch = +refs/heads/*:refs/remotes/origin/*
	url = [email protected]:joyent/node.git

Now add the line fetch = +refs/pull/*/head:refs/remotes/origin/pr/* to this section. Obviously, change the github url to match your project's URL. It ends up looking like this:

	# Video: http://rubyhoedown2008.confreaks.com/08-chris-wanstrath-keynote.html

	Hi everyone, I'm Chris Wanstrath.

	When Jeremy asked me to come talk, I said yes. Hell yes. Immediately. But
	then I took a few moments and thought, Wait, why? Why me? What am I supposed
	to say that's interesting? Something about Ruby, perhaps. Maybe the
	future of it. The future of something, at least. That sounds
	keynote-y.

	# Author: Pieter Noordhuis
	# Description: Simple demo to showcase Redis PubSub with EventMachine
	#
	# Update 7 Oct 2010:
	# - This example does not appear to work with Chrome >=6.0. Apparently,
	# the WebSocket protocol implementation in the cramp gem does not work
	# well with Chrome's (newer) WebSocket implementation.
	#
	# Requirements:
	# - rubygems: eventmachine, thin, cramp, sinatra, yajl-ruby

	Latency Comparison Numbers (~2012)
	----------------------------------
	L1 cache reference 0.5 ns
	Branch mispredict 5 ns
	L2 cache reference 7 ns 14x L1 cache
	Mutex lock/unlock 25 ns
	Main memory reference 100 ns 20x L2 cache, 200x L1 cache
	Compress 1K bytes with Zippy 3,000 ns 3 us
	Send 1K bytes over 1 Gbps network 10,000 ns 10 us
	Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD