jneira

(define (member-of-2? a lst1 lst2)
  (if (or (null? lst1) (null? lst2)) #f
    (or
     (and (eq? a (car lst1))
          (or (eq? a (car lst2))
              (member-of-2? a (list a) (cdr lst2))))
     (member-of-2? a (cdr lst1) lst2))))

jneira

type Instrument = String
type Account = String
type Quantity = BigDecimal
type Money = BigDecimal

import java.util.{Calendar, Date}
val today = Calendar.getInstance.getTime

case class Trade(ref: String, ins: Instrument, account: Account, unitPrice: Money,
  quantity: Quantity, tradeDate: Date = today) {

jneira

def ifM[B](t: => M[B], f: => M[B])(implicit a: Monad[M], b: A <:< Boolean): M[B] = 
  >>= ((x: A) => if (x) t else f)

jneira

;;1.45 Definir una macro MI-DO que tenga exactamente la misma funcionalidad que la macro DO, 
;;pero que además de devolver el valor correspondiente cuando se cumpla la condición de finalización,
;;devuelva un segundo valor que indique el número de iteraciones que se han realizado. No se deben 
;;utilizar las primitivas DO, DO*, DOLIST, DOTIMES.

(defmacro iterar (steps final &rest body)
  `(labels ((main ,(mapcar #'car steps)
                  (if ,(car final) ,(cadr final)
                    (progn ,@body
                           (main ,@(apply #'append

jneira

;; Ultimo commit con propuestas brillantes de http://twitter.com/_ogf_
(defn score-single [ps]
  (case ps 1 100 5 50 0))

(defn score-triple [ps]
  (case ps 1 1000 (* ps 100)))

(defn scores-by-freq [[ps freq]]
  [(* (quot freq 3)
      (score-triple ps))

jneira

(ns string-calc)

(defprotocol Adder
  (add [self]))

(extend-type java.lang.String
  Adder
  (add [s]
       (apply + (map #(Integer/parseInt %)
                     (.split s ",")))))

jneira

;;1.48 No todos los sistemas de LISP implementan el mecanismo
;;Backquote. Definir BACKQUOTE de forma que tenga el mismo
;;efecto que Backquote y permita manejar de forma apropiada
;;expresiones como COMA y COMA-AT de la forma que se
;;muestra en el siguiente ejemplo:
;;> (BACKQUOTE (A B (LIST ‘C ‘D) (COMA (LIST ‘E ‘F)
;;                               (COMA-AT (LIST ‘G ‘H)))
;;(A B (LIST ‘C ‘D) (E F) G H)

jneira

(defn fizz-buzz [n]
  (str (when (zero? (mod n 3)) "fizz") 
       (when (zero? (mod n 5)) "buzz")))

(defn fizz-buzz [n]
  (let [when-div-by 
          #(when (zero? (mod n %1)) %2) 
        join str]
    (join (when-div-by 3 "fizz") 
	  (when-div-by 5 "buzz"))))

jneira

(ns roman-numerals
  (:use clojure.test))

(def digits ["I" "IV" "V" "IX" "X" "XL" "L" "XC" "C" "CD" "D" "CM" "M"])
(def digits-ints (zipmap [1 4 5 9 10 40 50 90 100 400 500 900 1000] digits))

(defn floor [nums n]
  (first (filter #(<= % n) (reverse (sort nums)))))   

(defn from-int [n]

jneira

(defpackage game-of-life)

(defun get-neighbours (grid x y)
  (let ((result 0) (xo (- x 1))
        (yo (- y 1)))
    (dotimes (i 3)
      (dotimes (j 3)
        (let ((dx (+ xo i))
              (dy (+ yo j)))
          (when (and (array-in-bounds-p grid dx dy)