budu’s gists

budu / xkcd287.clj

Created April 17, 2012 02:24

Logic puzzle: XKCD #287 solution in Clojure core.logic

	(use 'clojure.core.logic)

	(def rvar? (comp not lvar?))

	(defmacro arithm [r x y op po]
	`(fn [a#]
	(let [r# (walk a# ~r)
	x# (walk a# ~x)
	y# (walk a# ~y)]
	(cond

budu / ComUtils.cs

Created April 12, 2012 19:40

Utility class to extract properties dynamically from a COM object. This provide a method that extract all of a given object properties (even those taking parameters) and generate a nice set of nested dictionnaries.

	public static class ComUtils
	{
	public static object Get(object obj, string key, object[] args = null)
	{
	return obj.GetType().InvokeMember(
	key,
	System.Reflection.BindingFlags.GetProperty,
	null,
	obj,
	args);

budu / send_more_money.clj

Created April 12, 2012 05:03

Logic puzzle: send more money solution in Clojure core.logic, translated from cKanren paper. Takes forever to run!

	(use 'clojure.core.logic
	'clojure.core.logic.arithmetic)

	(defne diffo
	[l]
	([[]])
	([[x]])
	([[x y . tail]]
	(fresh [l0 l1]
	(!= x y)

budu / attr_history.rb

Created March 3, 2012 18:03

Ruby Class mixin to create an accessor for which historical vales are kept in an Array, not thread-safe.

	module AttrHistory
	def attr_history(name)
	attr_reader "#{name}_history", name

	define_method "#{name}=" do \|value\|
	history = send("#{name}_history") \|\| []
	instance_variable_set "@#{name}_history", history.push(value)
	instance_variable_set "@#{name}", value
	end
	end

budu / factory.clj

Created December 21, 2011 03:35

A factory defining macro.

	(defmacro deffactory
	"Defines a factory function that returns an instance of the specified
	record initialized with the default values provided overridden by the
	values it is given."
	[factory-name record-name defaults]
	`(defn ~factory-name
	~(str "A factory function returning a new instance of " record-name
	" initialized with the defaults specified at the time of"
	" definition overridden by the given values. The values can"
	" be specified as a map or field-value pairs.")

budu / sicp.clj

Created September 4, 2011 23:56

Answers to exercises from chapter 1 of SICP in Clojure


	(ns sicp)

	;;;; Section 1.1 - The Elements of Programming


	;;; Exercise 1.1


	[10 12 8 3 6 'a 'b 19 false 4 16 6 16]

budu / SnakeMyTurnIn.hs

Created August 27, 2011 05:06

Snake my_turn_in puzzle implementation in Haskell

	-- Snake my_turn_in puzzle implementation
	--
	-- The direction argument accept an Ordering value where GT is
	-- :forward, LT is :backward and EQ is :same.
	--
	-- Problem definition can be found in:
	-- https://github.com/budu/Puzzles

	myTurnIn :: (Ord a, Integral a) => a -> a -> Ordering -> a -> a
	myTurnIn _ _ _ 1 = 0

budu / sy2.clj

Created May 4, 2011 01:11

Recursive implementation of Shunting-yard algorithm (refactored)

	(ns sy2 "based on: https://gist.github.com/953966")

	(defmacro if-eof [true-f false-f]
	`(try
	~false-f
	(catch Exception e#
	(if (= (.getMessage e#) "EOF while reading")
	~true-f
	(throw e#)))))

budu / sy.clj

Created May 3, 2011 00:08

Monadic implementation of the Shunting-yard algorithm

	(ns sy
	"Monadic implementation of the Shunting-yard algorithm, including
	infix binary operator with associativity, function calls and basic
	sequence support. It transalate a simple C like expression syntax into
	s-expression that can be evaluated by Clojure.

	1 + 2 => (+ 1 2)
	1 + 2 * 3 => (+ 1 (* 2 3))
	1 * 2 + 3 => (+ (* 1 2) 3)
	(1 + 2) * 3 => (* (identity (+ 1 2)) 3)

budu / crazy.clj

Created April 20, 2011 22:50

A macro which define a function and a macro that call that function passing the inner macro arguments and the form used to call it as the function arguments, or something like that.

	(defmacro crazy [name & args]
	(let [name* (symbol (str name \*))]
	`(do
	(defn ~name* [self# & params#]
	(prn self#))
	(defmacro ~name [~'& args#]
	`(~~name* (quote ~~'&form) ~@args#)))))

Nicolas Buduroi budu