How do I search for special characters in Clojure?

Question

Clojure uses a number of special characters such as

• ^String
• #(xyz ...)
• %&
• #_(some form here)
• >!

and many more. How can I search for documentation for these special characters, given that Google et al mostly ignore special characters in web pages and search strings?

Answer 1

This question and others have raised an important topic: it can often be difficult and frustrating to find documentation on special characters used in Clojure source code.

The first place to look is the Clojure docs themselves. There is even a special page devoted to this topic:

• https://clojure.org/guides/weird_characters

Many of the special characters are known as Reader Literals , which also have a documentation page:

• https://clojure.org/reference/reader

You can also find hints regarding special chars & their usage on:

• The Clojure CheatSheet
• ClojureDocs.org
• Clojure-Doc.org

Finally, the search engine SymbolHound.com can search for special symbols that Google & others ignore. For example, consider this Clojure code:

(defn lines
  "Given an open reader, return a lazy sequence of lines"
  [^java.io.BufferedReader reader]
  (take-while identity (repeatedly #(.readLine reader))))

How could we search for the meaning of ^java.io.BufferedReader on the 3rd line? If we go to SymbolHound and use the search string clojure ^ we get back:

---

270 results found for clojure ^

• What are the usages for ^ and how can I get more information on it?
• Clojure syntax question re: #^
• How do I dynamically find metadata for a Clojure function?

and many more answers.

Answer 2

They're all described here:

https://clojure.org/guides/weird_characters

You can also add more by contributing:

https://clojure.org/community/contributing_site