Character implementation in LispWorks covers the full range of the Unicode standard.
cl:char-code-limit is #x110000
, which covers exactly the Unicode range. The surrogate code points (codes #xd800
to #xdfff
) are illegal as character codes.
cl:code-char accepts integers from 0 below cl:char-code-limit. Other values cause an error. For codes in the surrogate range it returns nil
. Reading characters from streams and converting characters from foreign strings can generate characters in all the range (depending on the external-format used), and can never generate character objects corresponding to surrogate code points.
text-string and simple-text-string take 32 bits per character and can store the full range of Unicode characters.
simple-char is now a synonym for cl:character, and is deprecated.
16-bit characters and 16-bit strings are implemented by types bmp-char and bmp-string and simple-bmp-string (BMP is Basic Multilingual Plane, the first plane of Unicode, 0 - #xffff). You may want to use bmp-string to minimize memory usage if you have an application with many 16-bit strings. That will work provided all the characters you ever use have codes less than #x10000
. If all of the codes are below 256, you can use base-string instead.
Note: Character bits and font attributes are not supported. To deal with bits, use gesture-spec objects (see make-gesture-spec and coerce-to-gesture-spec).
LispWorks® User Guide and Reference Manual - 01 Dec 2021 19:30:24