chickadee » srfi-13 » string-upcase!

(string-upcase s [start end]) -> stringprocedure
(string-upcase! s [start end]) -> unspecifiedprocedure
(string-downcase s [start end]) -> stringprocedure
(string-downcase! s [start end]) -> unspecifiedprocedure

Raise or lower the case of the alphabetic characters in the string.

string-upcase and string-downcase return the result string and do not alter their S parameter. string-upcase! and string-downcase! are the in-place side-effecting variants.

These procedures use the locale- and context-insensitive 1-1 case mappings defined by Unicode's UnicodeData.txt table:

ftp://ftp.unicode.org/Public/UNIDATA/UnicodeData.txt