CLHS: Section 2.4.8.1

#

## 2.4.8.1 Sharpsign Backslash

Syntax: `#\<<`x`>>`

When the token x is a single character long, this parses as the literal character char. Uppercase and lowercase letters are distinguished after `#\`; `#\A` and `#\a` denote different character objects. Any single character works after `#\`, even those that are normally special to read, such as left-parenthesis and right-parenthesis.

In the single character case, the x must be followed by a non-constituent character. After `#\` is read, the reader backs up over the slash and then reads a token, treating the initial slash as a single escape character (whether it really is or not in the current readtable).

When the token x is more than one character long, the x must have the syntax of a symbol with no embedded package markers. In this case, the sharpsign backslash notation parses as the character whose name is `(string-upcase` x`)`; see Section 13.1.7 (Character Names).

For information about how the Lisp printer prints character objects, see Section 22.1.3.2 (Printing Characters).

The following X3J13 cleanup issues, not part of the specification, apply to this section:

- CHARACTER-LOOSE-ENDS:FIX
- CHARACTER-PROPOSAL:2-1-1

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