Simplified Common Lisp reference
Symbol class: Sequences (Lists, Strings) and Arrays
Symbol type: function
string-upcasestringstart(keyword)end(keyword) => string
Argument description:
string a string
start integer bouded by string length
end integer bouded by string length

STRING-UPCASE function converts string into its upcase reprezentation. returned. See also STRING-DOWNCASE, STRING-CAPITALIZE, CHAR-UPCASE and CHAR-DOWNCASE.

(string-upcase "some string") => "SOME STRING"
(string-upcase "some string" :start 2) => "soME STRING"
(string-upcase "some string" :start 2 :end 8) => "soME STRing"
Function indexFull documentation for string-upcase (HyperSpec)