Jason McClellan jmcclell

Advanced Functional Programming with Scala - Notes

1. Mastering Functions

A function is a mapping from one set, called a domain, to another set, called the codomain. A function associates every element in the domain with exactly one element in the codomain. In Scala, both domain and codomain are types.

val square : Int => Int = x => x * x

Concurrency Patterns in Go-Lang

Channels Primer

Creating Channels

Channels are created via the builtin make function. We specify the type as chan {datatype} where by {datatype} represents the type of data that can be written to and read from the channel.

	'''
	Template tag for returning Stackoverflow reputation

	Requires Py-StackExchange (https://github.com/lucjon/Py-StackExchange/)

	This isn't really meant to be consumed as-is for the following reasons:

	1. Built in logic for caching isn't ideal for making this distributable
	2. Having a template tag reach out to a 3rd party server could cause
	performance issues when rendering a template if the 3rd party server 404s

	{#
	This template snippet will take a page from a django Paginator and create a Twitter Bootstrap pagination HTML snippet.

	To use:

	{% include "path/to/django-paginator-bootstrap.html with page=contextVar only %}

	Optional variables:

	alignment - Accepts "centered" or "right". Other values have no affect. Default is left aligned.

	# FOS Rest
	fos_rest:
	param_fetcher_listener: true
	body_listener: true
	format_listener:
	rules:
	path: ~
	host: ~
	priorities:
	name: [json, html]

	class Rational(initialNumer: Int = 1, initialDenom: Int = 1) {
	require(initialDenom != 0, "denominator must be nonzero")

	private val gcd = {
	def gcdRec(x: Int, y: Int): Int = {
	if(y == 0) x else gcdRec(y, x % y)
	}
	abs(gcdRec(initialNumer, initialDenom))
	}

	<?php

	namespace JLM\SerializerExpressionBundle\ExpressionLanguage;

	use Symfony\Component\ExpressionLanguage\ExpressionLanguage as BaseExpressionLanguage;
	use Symfony\Component\ExpressionLanguage\Expression;

	use Symfony\Component\DependencyInjection\ContainerInterface;
	use Symfony\Component\ExpressionLanguage\ParserCache\ParserCacheInterface;

	Delete a line in a file (great for removing offending keys in known_hosts)

	sed -i.bak -e '134d' /root/.ssh/known_hosts

	will delete line #134 and back p the file as known_hosts.bak

	{% for image in images %}
	{% image image.input
	filter='jpegoptim' output=image.output %}
	<img src="{{ asset_url }}" alt={{ image.alt }}"/>
	{% endimage %}

	// image.input ex: @AcmeFooBundle/Resources/public/images/example.jpg
	// iamge.output ex: /images/example.jpg

	/**
	* @Route("/contact", name="_demo_contact")
	* @Template()
	*/
	public function contactAction(Request $request)
	{
	$contact = new Contact();
	// Set a default for message inside the data object itself.
	// I expect that if message is missing in the request, this value will be used as the default
	$contact->setMessage("Default message from controller");