Suhovius suhovius

A Primer on Ruby Method Lookup

Method lookup is a simple affair in most languages without multiple inheritance. You start from the receiver and move up the ancestors chain until you locate the method. Because Ruby allows you to mix in modules and extend singleton classes at runtime, this is an entirely different affair.

I will not build contrived code to exemplify the more complicated aspects of Ruby method lookup, as this will only serve to confuse the matter.

When you pass a message to an object, here is how Ruby finds what method to call:

1. Look within singleton class

GC.disable

Wall Clock Time versus CPU Time

An important difference to note is the how time is reported by various measurement methods. Wall clock time is the actual time passed in terms of human perception whereas CPU time is the time spent processing the work. CPU time doesn't include any delays waiting on resources to free up such as thread interrupts or garbage collection.

The Work to Measure

To keep things simple, we'll create a Ruby Proc and just repeatedly call that Proc for each of the measurement methods below.

Lambda: standard

# Creating a lambda
l = lambda { |name| "Hi #{name}!" }

# Executing the lambda
l.call("foo") # => Hi foo!

So I built a dummy Rails-plugin gem...

rails plugin new foo --skip-bundle -O --full

and filled in my .gemspec as below, including the line

s.add_dependency "rails-assets-sugar"

and added

	# read more at https://terrty.net/2014/ssl-tls-in-nginx/
	# latest version on https://gist.github.com/paskal/628882bee1948ef126dd/126e4d1daeb5244aacbbd847c5247c2e293f6adf
	# security test score: https://www.ssllabs.com/ssltest/analyze.html?d=terrty.net
	# your nginx version might not have all directives included, test this configuration before using in production against your nginx:
	# $ nginx -c /etc/nginx/nginx.conf -t

	server {
	# public key, contains your public key and class 1 certificate, to create:
	# (example for startssl)
	# $ (cat example.com.pem & wget -O - https://www.startssl.com/certs/class1/sha2/pem/sub.class1.server.sha2.ca.pem) \| tee -a /etc/nginx/ssl/domain.pem > /dev/null

	# Automatically instal the latest nginx
	wget -O - http://nginx.org/keys/nginx_signing.key \| sudo apt-key add -

	#Make a backup copy of your current sources.list file
	sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak

	#Now copy the following repositories to the end of ` /etc/apt/sources.list`
	echo "deb http://nginx.org/packages/mainline/ubuntu/ trusty nginx" \| sudo tee -a /etc/apt/sources.list
	echo "deb-src http://nginx.org/packages/mainline/ubuntu/ trusty nginx" \| sudo tee -a /etc/apt/sources.list

	# IE is still braindead so still use favicon.ico

	convert -resize x16 -gravity center -crop 16x16+0+0 -flatten -colors 256 input.png output-16x16.ico
	convert -resize x32 -gravity center -crop 32x32+0+0 -flatten -colors 256 input.png output-32x32.ico
	convert output-16x16.ico output-32x32.ico favicon.ico

	# Then, HTML needs to specify size="XxY" as largest size due to browser bugs

	<link rel="shortcut icon" href="/favicon.ico" sizes="32x32">

	::States = { AK: "Alaska",
	AL: "Alabama",
	AR: "Arkansas",
	AS: "American Samoa",
	AZ: "Arizona",
	CA: "California",
	CO: "Colorado",
	CT: "Connecticut",
	DC: "District of Columbia",
	DE: "Delaware",

	# This is the ONLY way I've found that works
	# All other suggested solutions (see below examples) don't actually work
	# And as an extra bonus: this deep copies as well!

	def deep_copy(o)
	Marshal.load(Marshal.dump(o))
	end

	git branch -m old_branch new_branch # Rename branch locally
	git push origin :old_branch # Delete the old branch
	git push --set-upstream origin new_branch # Push the new branch, set local branch to track the new remote