LISP: KEYWORD
[Typespec][CLTL 4]
SYNOPSIS:
keyword
DESCRIPTION:
This is the type specifier symbol which indicates the set of keyword symbols.
SEE ALSO
keywordp.
LISP: KEYWORDP
C: Lkeywordp
min args: 1
max args: 1
[F][CLTL 10]
SYNOPSIS:
keywordp object
DESCRIPTION:
The predicate keywordp returns t if the argument is a symbol which belongs to the keyword package. Keyword symbols are written with a leading colon. The argument may be any LISP object.
Every keyword is a constant, an object which always evaluates to itself; hence it does not need to be quoted. This makes their use convenient when you want to use a symbol which 'stands for itself', one which is used only for its name. It is an error to try to assign a value to a keyword symbol since it is a constant.
EXAMPLES:
(keywordp :foo) => T ; does not need to be quoted
(keywordp 'foo) => NIL ; symbol needs to be quoted
NOTES:
Note that internally keyword printnames do not have a colon; the colon is an artifact of the package system which indicates that the symbol belongs to the keyword package.
(symbol-name :foo) => "FOO"