polytypic

A pattern for using GADTs to subset cases

Consider the following straightforward mutable queue implementation using two stacks:

type 'a adt_queue = {
  mutable head : 'a head;
  mutable tail : 'a tail;
}

rosario

Eric Elliott's "Composing Software" Series

A collection of links to the excellent "Composing Software" series of medium stories by Eric Elliott.

• The Rise and Fall and Rise of Functional Programming
• Why Learn Functional Programming in JavaScript?
• A Functional Programmer’s Introduction to JavaScript
• Higher Order Functions
• Reduce
• Functors & Categories
• [Composing

swlaschin

Functional Track talks from NDC Oslo 2016

Wednesday 2016-06-08

• What every Node.js developer needs to know about Elixir - Bryan Hunter
• F# in the Real World - Yan Cui
• Functional Programming for Mobile Apps - Frank A. Krueger
• Phoenix a web framework for the new web - José Valim
• REPL Driven Development, Scrum, and the Wright Brothers - Jamie Dixon

jbgi

import static java.lang.System.*;

import java.util.function.BiFunction;
import java.util.function.Function;

// Implementation of a pseudo-GADT in Java, translating the examples from
// http://www.cs.ox.ac.uk/ralf.hinze/publications/With.pdf
// The technique presented below is, in fact, just an encoding of a normal Algebraic Data Type
// using a variation of the visitor pattern + the application of the Yoneda lemma to make it
// isomorphic to the targeted 'GADT'.

mjkoo

#!/usr/bin/env python2

# NOTE: Use of this script is deprecated, instead I recommend you use
#
# $ unzip -LL eui_v1_20.zip -d "$HOME/.steam/steam/SteamApps/common/Sid Meier's Civilization V/steamassets/assets/dlc"
#
# to make use of the unzip command's built-in conversion to lowercase filenames
# (thanks reddit user /u/xkero and github user Mfdas)

import os

shangaslammi

s x y z = x z (y z)
k x y   = x
i       = s k k
c       = s (s (k (s (k s) k)) s) (k k)
b       = s (k s) k

hello =
    s(s(k s)(s(k k)(s(k s)(s(k(s(k s)))(s(s(k s)(s(k k)(s(k b)i)))(k(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s
    b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(c k))))))))))))))))))))))))))))))))))))))))))
    )))))))))))))))))))))))))))(s(s(k s)(s(k k)(s(k s)(s(k(s(k s)))(s(s(k s)(s(k k)(s(k b)i)))(k(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s b(s

ticean

Create Git Mirror from SVN Repository

This guide will demonstrate how to mirror an SVN into a Git repo. You're the target audience if you're an SVN user, just getting started with Git and need to coax your project team over to Git.

The branching scenario has been simplified for clarity.

References