Common Lisp tips

Let’s all share Common Lisp tips, in the spirit of https://lisptips.com/ and https://slime-tips.tumblr.com/.

Share a new tip in the issues !

Issues act as a blogging platform: everybody can post a new tip,
we tag it, then we can upvote and downvote, browse the tips with
filters and subscribe to new posts.

Although sharing quick tips is cool and useful, don’t forget to
enhance the documentation out there ;)

We could eventually transform them to a static website, if there is interest (for example, with Glyph).

Mandatory CL resources:

• http://common-lisp.net/
• http://lisp-lang.org/
• http://quickdocs.org/
• https://lispcookbook.github.io/cl-cookbook/
• https://github.com/CodyReichert/awesome-cl

Community:

• https://www.reddit.com/r/Common_Lisp
• http://www.lispforum.com/
• #lisp on freenode

To ask questions:

• https://www.reddit.com/r/learnlisp/
• https://stackoverflow.com/questions/tagged/common-lisp

and the above.