juan-reynoso

;; list to string

CL-USER>  (map 'string (lambda (x) (char (write-to-string x) 0)) '(1 2 3))
"123"


;; string to list

CL-USER> (map 'list (lambda (x) (intern (string-upcase (string x)))) "lisp")
(L I S P)

juan-reynoso

;;;;  Condition Handler
;;;; The macro HANDLER-CASE establishes this kind of condition handler.

;;;; The basic form of a HANDLER-CASE is as follows:
;;;; (handler-case expression
;;;;   error-clause*)

;;;; where each error-clause is of the following form:
;;;; (condition-type ([var]) code)

juan-reynoso

How to install and configure your IDE for Common Lisp

SBCL

SBCL is a high performance Common Lisp compiler.

http://www.sbcl.org/

SBCL installation as super user (root)

You need to run the commands as super user (root)

Download

juan-reynoso

;;;; The Standard Method Combination

(defclass book ()
  ((name :accessor book-name
	 :initarg :book-name)))

;;; Create an object
(defparameter *book* (make-instance 'book
				    :book-name "The Art of the Metaobject Protocol"))

juan-reynoso

(in-package :postmodern)

(defvar *db-parameters* '("my_database" "lisp_user" "your-secret" "localhost" :POOLED-P T)
  "Information about the connection of database.")

(defparameter *my-fruit* nil
  "This var will has an object of fruits.")

;;; Define the macro to connect to the postgresql server
(defmacro with-database (&body query)

juan-reynoso

;;; A generic function specifies only the interface.
;;; It performs a high-level operation.

;;; Generic functions are functions that behave differently
;;; depending on the type and identity of the arguments. 
(defgeneric say-type-of-object (x)
  (:documentation "It displays the type of an object."))

;;; The implementation of a generic function does not exist in one place; it
;;; is distributed across a set of methods.

juan-reynoso

(defun copy-a-file (origin-path new-path)
  "Copy a file"
  (let ((value-from-read-byte nil))
    ;; create a stream which reads a file
    (with-open-file (origin-file origin-path :direction :input
					     :element-type 'unsigned-byte)
      ;; create a stream which write into a file
      (with-open-file (new-file new-path :direction :output
					 :element-type 'unsigned-byte
					 :if-exists :supersede)

juan-reynoso

(defparameter *line* nil "This is a global variable")

;;; an example
(with-open-file (file "/tmp/myfile.txt" :direction :input)
  (loop
    ;; gets a line from the file
    (setf *line* (read-line file nil))
    (if *line*
	;; print the lines stored in the text file
	(format t "~% ~a ~%" *line*)

juan-reynoso

# Python Object-Oriented programming

# Define a class called Dog
# Python class names are written in CapitalizedWords notation by convention. 
class Dog:
    # define a method called __init__ it is a special init method.
    # "__init__" is a reseved method in python classes. It is known as a constructor in object oriented concepts.
    # This method called when an object is created from the class and it allow the class to initialize the attributes of a class.
    def __init__ (self, name, age):
        # self represents the instance of the class. By using the "self" keyword. We can access the attibutes and methods of the

juan-reynoso

/* Creates a single object, using an object literal.
 * An object literal is a list of name:value pairs 
   (like age:36) inside curly braces {}.
*/

let myObjectPerson = { name: 'Juan', age: 36, sayHello: function (){
    console.log("Hello, I am " + this.name + " and I am " +
		this.age + " years old.");}
	       };