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Common Lisp

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A programmable programming language.
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Track mentors

5 Mentors

Our mentors are friendly, experienced Common Lisp developers who will help teach you new techniques and tricks.
Track students

2,092 Students

Join thousands of students who have enjoyed learning and improving their skills by taking this track.
Track exercises

43 Exercises

Hundreds of hours have gone into making these exercises fun, useful, and challenging to help you enjoy learning.

About Common Lisp

(defun distance (str1 str2
                 &key (test #'char=))
  "Number of positional differences in
   two equal length strings."
  (when (= (length str1) (length str2))
    (count nil
           (map 'list test str1 str2))))

Common Lisp is an offshoot of the long-running family of Lisp programming languages. It's a multi-paradigm programming language that allows you to choose the approach and paradigm according to your application domain.

Common Lisp has fast prototyping capabilities, and exceptional support for object oriented programming. It also boasts a macro system which allows you to adapt the language to your needs, and a run-time environment which allows modification of running applications.

To learn more about Common Lisp, take a look at the Common Lisp homepage.

Join the Common Lisp track

Exercism is a great website

Exercism is a great website where I was able to have some very interesting challenges.

Bud Chirica, Scotland
Relaxed. Encouraging. Supportive.

Meet the Common Lisp Track mentors

Once you join the Common Lisp language track, you will receive support and feedback from our team of mentors. Here are the bios of a few of the mentors of this track.

Avatar of Tim Hawes

Tim Hawes https://github.com/timotheosh

I love Lisp, functional programming, and the nostalgia behind Common Lisp.
Avatar of Tushar Tyagi

Tushar Tyagi https://github.com/tushartyagi

I dabble with Common Lisp and find it interesting because of minimal syntax and the amazing functionalities which the syntax brings.
Avatar of Pierre Thierry

Pierre Thierry https://github.com/kephas

I fell in love with Common Lisp for its interactivity, metaprogramming and uniform syntax. If I have any say, it's usually my language of choice for both professional and personal projects.
Avatar of Mark Simpson

Mark Simpson https://github.com/verdammelt

I have always been interested in Lisps since taking the SICP course in college. I love the expressiveness and conciseness of the simple syntax, and the ability to build the language upward to meet the domain.
Avatar of Brooks J Rady

Brooks J Rady thelostlambda.xyz

Lover of functional programming, writing code that writes code for me, and (evidently) parentheses.
Fun. Challenging. Interesting

Community-sourced Common Lisp exercises

These are a few of the 43 exercises on the Common Lisp track. You can see all the exercises here.

ETL
easy
maps
transforming
loops
Binary
easy
bitwise operations
integers
math
conditionals
Gigasecond
easy
integers
time
transforming
variables
dates
Prime Factors
easy
filtering
integers
maps
math
conditionals
loops
Allergies
easy
bitwise operations
integers
text formatting
conditionals
Difference Of Squares
easy
floating point numbers
integers
math
loops
Passionate. Knowledgeable. Creative.

Meet the Common Lisp Track maintainers

The Common Lisp Maintainers are the brains behind the Common Lisp Track. They spend their spare time creating interesting and challenging exercises that we can all learn from. We are incredibly grateful for their hard work. Here are the bios of a few of the maintainers of this track.

Avatar of Mark Simpson

Mark Simpson Code and Cocktails

I have always been interested in Lisps since taking the SICP course in college. I love the expressiveness and conciseness of the simple syntax, and the ability to build the language upward to meet the domain.
Avatar of Thomas de Grivel

Thomas de Grivel http://kmx.io/

I'm writing Rails on Lisp, Facts, Adams and CFFI-POSIX as open-source projects in Common Lisp.

Get started with the Common Lisp track. As with everything on Exercism, it's 100% free!

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