Common Lisp Programming Download Pdf: The Ultimate Guide for Beginners and Experts

``` You can access the slots of an instance using the reader methods: ```lisp (person-name *) ``` ```lisp "Alice" ``` Common Lisp has many data types and structures that you can use to store and manipulate data. Some of the most common ones are: - Lists: A list is a sequence of elements enclosed by parentheses. For example: `(1 2 3)`, `(a b c)`, `(hello world)`. You can create lists using the `list` function or the quote operator `'`. You can access the elements of a list using the `car` and `cdr` functions or the `nth` function. You can modify a list using the `setf` function or the `push` and `pop` macros. - Vectors: A vector is a sequence of elements enclosed by square brackets. For example: `[1 2 3]`, `[a b c]`, `[hello world]`. You can create vectors using the `vector` function or the `#(` syntax. You can access the elements of a vector using the `aref` function or the `elt` function. You can modify a vector using the `setf` function or the `vector-push` and `vector-pop` functions. - Hashes: A hash is a collection of key-value pairs enclosed by curly braces. For example: `:name "Bing" :age 10`, `1 "one" 2 "two"`, `:a 1 :b 2 :c 3`. You can create hashes using the `make-hash-table` function or the `#{` syntax. You can access the values of a hash using the `gethash` function or the `getf` function. You can modify a hash using the `setf` function or the `remhash` function. - Strings: A string is a sequence of characters enclosed by double quotes. For example: `"Bing"`, `"Hello world"`, `"This is a string"`. You can create strings using the `string` function or the double quote syntax. You can access the characters of a string using the `char` function or the `aref` function. You can modify a string using the `setf` function or the `replace` function Common Lisp has many control structures that allow you to control the flow of execution of your code. Some of the most common ones are: - Conditionals: Common Lisp has several conditional constructs that allow you to execute different branches of code depending on some conditions. The simplest one is `if`, which has the form `(if test then [else])` and evaluates to `then` if `test` is true and `else` otherwise. The `else` part can be omitted. For example: ```lisp (if (> 3 2) "Three is bigger!" "Two is bigger!") ;;=> "Three is bigger!" ``` Another conditional construct is `cond`, which has the form `(cond (test-1 consequent-1-1 consequent-1-2 ...) (test-2 consequent-2-1 ...) ...)` and evaluates the first clause whose `test` is true and returns the value of the last consequent in that clause. For example: ```lisp (cond ((> 3 4) "Three is bigger than four!") ((> 3 3) "Three is bigger than three!") ((> 3 2) "Three is bigger than two!") ((> 3 1) "Three is bigger than one!")) ;;=> "Three is bigger than two!" ``` To provide a default clause to evaluate if no other clause evaluates to true, you can add a clause that uses `t` as the test. For example: ```lisp (cond ((= n 1) "N equals 1") (t "N doesn't equal 1")) ``` If you only need one clause, you can use `when` or `unless`, which have the form `(when test consequent-1 consequent-2 ...)` and `(unless test consequent-1 consequent-2 ...)`. They evaluate the consequents only if the test is true or false respectively. For example: ```lisp (when (> 3 4) "Three is bigger than four.") ;;=> NIL (when ( "Two is smaller than five." (unless (> 3 4) "Three is not bigger than four.") ;;=> "Three is not bigger than four." (unless ( NIL ``` - Loops: Common Lisp has several looping constructs that allow you to repeat a block of code until some condition is met or for a fixed number of times. The most basic one is `do`, which has the form `(do (varlist) (endlist) &body)` and executes the body repeatedly while updating the variables in varlist according to their initial values and step forms. The endlist contains the end condition and the return value of the loop. For example: ```lisp (do ((i 0 (+ i 1)) (sum 0 (+ sum i))) ((>= i 10) sum)) ;;=> 45 ``` This loop iterates over the values of i from 0 to 9 and accumulates their sum in sum. It returns the value of sum when i reaches 10. Another looping construct is `loop`, which has a more expressive syntax that allows you to specify various aspects of the loop such as iteration variables, termination conditions, accumulation clauses etc. For example: ```lisp (loop for i from 0 below 10 for j from i downto 0 collect (* i j)) ;;=> (0 0 1 0 2 4 0 3 6 9) ``` This loop iterates over two variables i and j and collects their products in a list. Other looping constructs include `dotimes`, which executes a body for a fixed number of times, and `dolist`, which executes a body for each element of a list. For example: ```lisp (dotimes (i 5) (print i)) ;; Prints: ;;0 ;;1 ;;2 ;;3 ;;4 ;;=> NIL (dolist (x '(a b c)) (print x)) ;; Prints: ;;A ;;B ;;C ;;=> NIL ``` - Blocks and Exits: Common Lisp has a mechanism to define blocks of code that can be exited prematurely using the `return-from` form. A block is defined using the `block` form, which has the name of the block and the body of the block. For example: ```lisp (block foo (print "Hello") (return-from foo "Bye") (print "World")) ;; Prints: ;;Hello ;;=> "Bye" ``` This block has the name foo and prints "Hello" before returning "Bye" and exiting the block. The last print statement is never executed. You can also use `return` as a shorthand for `return-from` if the block name is nil. For example: ```lisp (block nil (print "Hello") (return "Bye") (print "World")) ;; Prints: ;;Hello ;;=> "Bye" ``` This is equivalent to the previous example. - Multiple Values: Common Lisp has a feature that allows you to return and bind multiple values from a form. You can use the `values` form to return multiple values from a form. For example: ```lisp (values 1 2 3) ;;=> 1, 2, 3 ``` This returns three values: 1, 2, and 3. You can use the `multiple-value-bind` form to bind multiple values to variables. For example: ```lisp (multiple-value-bind (a b c) (values 1 2 3) (+ a b c)) ;;=> 6 ``` This binds the values 1, 2, and 3 to the variables a, b, and c respectively and evaluates the body with those bindings. You can also use the `multiple-value-list` form to collect multiple values into a list. For example: ```lisp (multiple-value-list (values 1 2 3)) ;;=> (1 2 3) ``` This returns a list of the values returned by the form. ## Common Lisp Advanced Topics Common Lisp is a very expressive and powerful language that allows you to use multiple paradigms and customize its behavior to suit your needs. Some of the advanced topics that you can explore in Common Lisp are: - Multiple Paradigms: Common Lisp supports multiple programming paradigms such as functional, object-oriented, meta-programming, concurrent, and logic programming. You can choose the paradigm that best fits your problem domain or combine them in creative ways. Functional programming is a paradigm that emphasizes the use of pure functions that do not have side effects and operate on immutable data. Common Lisp supports functional programming by providing first-class functions, higher-order functions, lambda expressions, closures, recursion etc. For example, you can use the `mapcar` function to apply a function to each element of a list and return a new list: ```lisp (mapcar #'string-upcase '("hello" "world")) ;;=> ("HELLO" "WORLD") ``` Object-oriented programming is a paradigm that emphasizes the use of objects that encapsulate data and behavior. Common Lisp supports object-oriented programming by providing CLOS (Common Lisp Object System), which is a powerful and flexible system for defining and manipulating objects and methods. For example, you can use CLOS to define a class that inherits from another class and overrides some of its methods: ```lisp (defclass animal () ((name :reader animal-name :initarg :name))) (defclass dog (animal) ((breed :reader dog-breed :initarg :breed))) (defmethod speak ((a animal)) (format t "A says nothing%" (animal-name a))) (defmethod speak ((d dog)) (format t "A barks%" (animal-name d))) (let ((a (make-instance 'animal :name "Bob")) (d (make-instance 'dog :name "Rex" :breed "Labrador"))) (speak a) (speak d)) ;; Prints: ;;Bob says nothing ;;Rex barks ;;=> NIL ``` Meta-programming is a paradigm that involves writing code that manipulates or generates other code. Common Lisp supports meta-programming by providing a powerful macro system that allows you to create new syntax and transform code at compile-time. For example, you can use macros to define a new control structure that executes a body only if an expression is not nil: ```lisp (defmacro when-not (test &body body) `(unless ,test ,@body)) (when-not nil (print "This will be executed")) ;; Prints: ;;This will be executed ;;=> NIL (when-not t (print "This will not be executed")) ;;=> NIL ``` Concurrent programming is a paradigm that involves writing code that can run in parallel or asynchronously. Common Lisp supports concurrent programming by providing various features such as threads, locks, channels, futures etc. ## Common Lisp Applications Common Lisp is a general-purpose language that can be used for a wide range of applications and domains. In this section, we will show you some examples of how to use Common Lisp for web development, artificial intelligence, data analysis, and game development. ### Web Development Web development is one of the most popular and practical applications of Common Lisp today. There are many libraries and frameworks that allow you to create web applications using Common Lisp. Some of the most notable ones are: - Hunchentoot: Hunchentoot is the de-facto web server for Common Lisp. It provides a low-level interface for handling HTTP requests and responses, as well as various features such as session management, authentication, SSL support etc. You can use Hunchentoot as a standalone server or behind a proxy server such as Apache or Nginx. You can also use Hunchentoot to define routes or handlers for different URLs using its easy-routes library. - Clack: Clack is a web application environment that abstracts away the details of different web servers and provides a unified interface for web applications. It is similar to WSGI in Python or Rack in Ruby. Clack supports various web servers such as Hunchentoot, Wookie, Woo etc. You can use Clack to write portable web applications that can run on different servers without changing the code. - Caveman2: Caveman2 is a web framework that builds on top of Clack and provides a high-level interface for web development. It follows the MVC (Model-View-Controller) pattern and provides features such as routing, templating, database access, validation etc. Caveman2 is inspired by Ruby on Rails and Django and aims to be simple and easy to use. - Snooze: Snooze is another web framework that builds on top of Clack and provides a RESTful interface for web development. It allows you to define resources and methods using annotations and provides features such as routing, content negotiation, authentication etc. Snooze is inspired by JAX-RS and Flask and aims to be flexible and expressive. - Radiance: Radiance is a web framework that builds on top of Clack and provides a modular and extensible interface for web development. It allows you to define applications as modules that can be loaded and unloaded dynamically and provides features such as routing, configuration, logging etc. Radiance is inspired by Racket and aims to be powerful and scalable. ### Artificial Intelligence Artificial intelligence is one of the original domains of Common Lisp and one of its strengths today. There are many libraries and frameworks that allow you to use Common Lisp for artificial intelligence and machine learning. Some of the most notable ones are: - cl-ml: cl-ml is a machine learning library that provides various algorithms and utilities for supervised and unsupervised learning, such as classification, regression, clustering etc. It also provides interfaces to external libraries such as TensorFlow, Scikit-Learn etc. - cl-nlp: cl-nlp is a natural language processing library that provides various tools and resources for processing natural language data, such as tokenization, tagging, parsing etc. It also provides interfaces to external libraries such as Stanford CoreNLP, spaCy etc. - cl-neural-networks: cl-neural-networks is a neural network library that provides various models and layers for building neural networks, such as feedforward networks, recurrent networks, convolutional networks etc. It also provides interfaces to external libraries such as Keras, PyTorch etc. ### Data Analysis Data analysis is another popular and practical application of Common Lisp today. There are many libraries and frameworks that allow you to use Common Lisp for data analysis and visualization. Some of the most notable ones are: - cl-plot: cl-plot is a plotting library that provides various functions and macros for creating plots and charts using different backends such as Gnuplot, Matplotlib etc. It also provides interfaces to external libraries such as Plotly etc. - cl-dataframe: cl-dataframe is a data frame library that provides various functions and macros for manipulating tabular data using different backends such as SQLite, PostgreSQL etc. It also provides interfaces to external libraries such as Pandas etc. - cl-notebook: cl-notebook is a notebook library that provides a web-based interface for interactive data analysis and visualization using Common Lisp. It is similar to Jupyter Notebook and allows you to write and execute Common Lisp code, display plots and charts, and share your results. ### Game Development Game development is another fun and creative application of Common Lisp today. There are many libraries and frameworks that allow you to use Common Lisp for game development. Some of the most notable ones are: - cl-sdl2: cl-sdl2 is a binding library that provides access to the SDL2 library, which is a cross-platform library for low-level multimedia programming. It allows you to create windows, handle events, render graphics, play sounds etc. - cepl: cepl is a game engine library that builds on top of cl-sdl2 and provides a high-level interface for game development. It allows you to write and run OpenGL code interactively using the REPL, create scenes, entities, cameras etc. - sketch: sketch is a game framework library that builds on top of cepl and provides a simple and easy interface for game development. It allows you to write games using a functional style, create sprites, animations, sounds etc. ## Conclusion In this article, we have covered some of the basics and advanced topics of Common Lisp programming. We have also shown you how to use Common Lisp for different applications such as web development, artificial intelligence, data analysis, and game development. By now, you should have a good understanding of Common Lisp and how to use it effectively. However, this article is not meant to be exhaustive or comprehensive. There are many more topics and features that we have not covered here. Common Lisp is a rich and powerful language that has a lot to offer to programmers of all levels and domains. If you want to learn more about Common Lisp, here are some resources and links that you can check out: - The Common Lisp Cookbook: https://lispcookbook.github.io/cl-cookbook/ - Practical Common Lisp: http://www.gigamonkeys.com/book/ - Land of Lisp: http://landoflisp.com/ - Awesome Common Lisp: https://github.com/CodyReichert/awesome-cl - Common Lisp Reddit: https://www.reddit.com/r/Common_Lisp/ We hope that this article has sparked your interest in Common Lisp and encouraged you to try it out for yourself. Common Lisp is a fun and rewarding language that will challenge you and expand your horizons as a programmer. Happy hacking! ## FAQs - What are some of the best books on Common Lisp programming? Some of the best books on Common Lisp programming are: - Practical Common Lisp by Peter Seibel: This book is a practical introduction to Common Lisp that covers various topics such as data structures, macros, web development etc. It also includes several real-world examples and projects that you can follow along. - Land of Lisp by Conrad Barski: This book is a fun and engaging introduction to Common Lisp that covers various topics such as recursion, functional programming, game development etc. It also includes several games and cartoons that you can play and enjoy. - ANSI Common Lisp by Paul Graham: This book is a comprehensive reference to Common Lisp that covers various topics such as syntax, semantics, data types, control structures etc. It also includes several exercises and examples that you can practice. - What are some of the most popular Common Lisp projects and applications? Some of the most popular Common Lisp projects and applications are: - Maxima: Maxima is a computer algebra system that can perform symbolic and numerical computations such as calculus, linear algebra, differential equations etc. - ITA Software: ITA Software (now Google) developed Matrix, a flight search engine that uses Common Lisp to perform complex queries and optimizations. - Grammarly: Grammarly is a grammar checking service that uses Common Lisp to perform natural language processing and machine learning tasks. - ABCL: ABCL (Armed Bear Common Lisp) is a Common Lisp implementation that runs on the Java Virtual Machine and can interoperate with Java libraries and frameworks. - Roswell: Roswell is a command-line tool that allows you to install and manage Common Lisp implementations and libraries easily. - What are some of the differences between Common Lisp and other Lisp dialects such as Scheme or Clojure? Some of the differences between Common Lisp and other Lisp dialects are: - Syntax: Common Lisp has a more complex syntax than Scheme or Clojure, which have simpler and more consistent syntaxes. For example, Common Lisp has multiple ways to define functions (`defun`, `lambda`, `flet` etc.), while Scheme or Clojure have only one way (`lambda` or `fn`). - Standardization: Common Lisp has an official ANSI standard that defines its features and behavior, while Scheme or Clojure do not have official standards (although Scheme has several de facto standards such as R5RS or R6RS). This means that Common Lisp implementations are more compatible with each other than - Challenges or Drawbacks: Common Lisp is not a perfect language and it has some challenges or drawbacks that you should be aware of. Some of them are: - Popularity: Common Lisp is not a very popular language today and it has a relatively small user base and community compared to other languages. This means that you might have less resources, support, and opportunities available to you as a Common Lisp programmer. You might also face some prejudice or resistance from other programmers or employers who are not familiar with or appreciate Common Lisp. - Complexity: Common Lisp is a very complex language that has many features and options that can be overwhelming or confusing for beginners or even experienced programmers. You might have to learn a lot of syntax, semantics, idioms, libraries etc. to master Common Lisp. You might also have to deal with some legacy or deprecated features that are still part of the standard but not widely used or recommended today. - Portability: Common Lisp is a portable language that can run on different platforms and environments, but it is not always easy or straightforward to achieve portability. You might have to deal with some differences or incompatibilities between different Common Lisp implementations or libraries. You might also have to use some external tools or libraries to access some platform-s