shubham shkesar

The thing that students have the hardest time on when learning functional programming is how to process a recursive structure while maintaining some sort of "state", the result if you will. I'll attempt here to demystify the process.

Functional programming languages almost always use a lot of recursively defined structures. Depending on the language those can be implemented in various ways, but in any case the end result is the same. A structure of this type is either an "atom", i.e. an irreducible thing, or a "compound" consisting of substructures of the same form.

For example a "list" is either an Empty/Nil list (the "atom") or it is formed as a Cons of a value and another list (compound form). That other "sublist" can itself be empty or another cons and so on and so forth. A tree is similar. It is either empty, or it consists of a triple of a value and two sub-trees, left and right.

Almost every problem we encounter is a question about doing something with all entries in a structure. To solve these prob

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.

jame@out.org	Stefanie	House
dolores.bernice@roofroom.me	Dinah	Erickson
luke.homer.gerard@smile.info	Melisa	Reynolds
salvador.perry@selectionself.info	Lily	Carson
rich.jamel@cover.me	Millard	Rubio
benita@rangerat.edu	Octavia	Santana
vickie.mattie@westwet.info	Royal	Bender
dwayne@part.me	Laverne	Hutchins
jeanette.laurie.katie@light.me	Sherman	Wilder
jami.elnora@smokesmooth.edu	Thelma	Burris

	#!/usr/bin/python
	# -- coding: utf-8 --

	import subprocess


	__all__ = ["transform"]
	__version__ = '0.3'
	__author__ = 'Christoph Burgmer <cburgmer@ira.uka.de>'
	__url__ = 'http://github.com/cburgmer/upsidedown'

	@Command(command="save", aliases="s,sv")
	public void save() {
	player.save();
	}

	public void setup() {
	list<Method> commands = getAllAnnotatedMethods();
	for(Method m : commands) {
	commandmap.put(m.getAnnotation().command(), m);
	}

	package controllers

	import org.squeryl.PrimitiveTypeMode._
	import org.squeryl.{Session}

	import play.api._
	import play.api.mvc._

	import models._

	#This script reads all files in all directories of the folder taken from the openClassroom site and generates the dictionary, which we can then store in a file
	folders = ["spam-train","spam-test","nonspam-train","nonspam-test"]
	import os,sys
	#We need a dictionary to store word occurences. What we can do is create a default dict and then update the frequencies. Write it all into a file all at once.
	from collections import *
	dictionary = defaultdict(int)
	fdict = open(sys.argv[2],'w') #File to write all the entries in the dictionary
	for root,dirnames,filenames in os.walk(sys.argv[1]):
	for d in dirnames: #For each directory
	for f in os.listdir(d):